Revert of SkLiteDL: turn vtable sideways (patchset #7 id:120001 of https://codereview.chromium.org/2231103002/ )

Reason for revert:
speculative revert to fix DEPS roll

Original issue's description:
> SkLiteDL: turn vtable sideways
>
> Instead of using virtuals for polymorphism, store each polymorphic operation
> in its own array of function pointers.  This removes an indirection when calling
> the function, and lets us use nullptr as a signal to skip the call entirely.
>
> Unfortunately (as the old code is rather simpler) this makes an unambiguous speed improvement.
>
> Before:
> curr/maxrss	loops	min	median	mean	max	stddev	samples	config	bench
>   21/26  MB	2	44.6µs	46.4µs	48.3µs	274µs	13%	51724	nonrendering	desk_nytimes.skp
>   23/26  MB	11	11.4µs	11.9µs	12.4µs	75.1µs	15%	36716	nonrendering	keymobi_nytimes_com_.skp
>
> After:
>   19/26  MB	4	40.4µs	41.6µs	42.5µs	197µs	10%	29379	nonrendering	desk_nytimes.skp
>   20/26  MB	14	10.5µs	10.7µs	11.2µs	59.5µs	13%	31971	nonrendering	keymobi_nytimes_com_.skp
>
> Broader comparison:
>                keymobi_linkedin.skp	1.76us -> 1.77us	1x
> keymobi_bing_com_search_q_sloth.skp	5.09us -> 5.05us	0.99x
>                keymobi_digg_com.skp	17.4us -> 17.3us	0.99x
>            keymobi_theverge_com.skp	3.37us -> 3.34us	0.99x
> top25desk_mail_google_com_mail_.skp	30.8us -> 30.4us	0.99x
>                      tabl_gmail.skp	3.44us -> 3.38us	0.98x
>     top25desk_wikipedia__1_tab_.skp	 100us -> 97.7us	0.98x
> keymobi_cnn_com_2012_10_03_poli.skp	52.9us -> 51.7us	0.98x
>                 desk_chalkboard.skp	 107us ->  104us	0.97x
>              desk_css3gradients.skp	17.8us -> 17.3us	0.97x
> keymobi_androidpolice_com_2012_.skp	42.3us -> 41.1us	0.97x
>                 desk_googlehome.skp	1.94us -> 1.88us	0.97x
>                keymobi_mlb_com_.skp	5.38us -> 5.18us	0.96x
>             top25desk_pinterest.skp	92.1us -> 88.5us	0.96x
> keymobi_iphone_capitolvolkswage.skp	15.1us -> 14.5us	0.96x
>          keymobi_techcrunch_com.skp	9.45us -> 9.05us	0.96x
>                       desk_espn.skp	31.3us ->   30us	0.96x
>           keymobi_slashdot_org_.skp	8.72us -> 8.34us	0.96x
>                  desk_tiger8svg.skp	30.6us -> 29.2us	0.96x
>                 keymobi_blogger.skp	4.09us -> 3.91us	0.95x
> keymobi_baidu_com_s_wd_barack_o.skp	11.9us -> 11.3us	0.95x
>        keymobi_cuteoverload_com.skp	54.2us -> 51.6us	0.95x
>         keymobi_deviantart_com_.skp	17.2us -> 16.4us	0.95x
>                     desk_mapsvg.skp	 163ns ->  155ns	0.95x
>               keymobi_pinterest.skp	6.97us -> 6.62us	0.95x
>       top25desk_games_yahoo_com.skp	94.1us -> 89.3us	0.95x
>  top25desk_google_com_calendar_.skp	  18us ->   17us	0.95x
> keymobi_google_co_uk_search_hl_.skp	11.4us -> 10.8us	0.95x
>                     tabl_pravda.skp	38.5us -> 36.4us	0.94x
>                desk_gmailthread.skp	  19us -> 17.9us	0.94x
> keymobi_reddit_com_r_programmin.skp	76.1us -> 71.7us	0.94x
>              top25desk_linkedin.skp	  20us -> 18.8us	0.94x
>                tabl_gamedeksiam.skp	 118us ->  112us	0.94x
>          keymobi_boingboing_net.skp	20.4us -> 19.1us	0.93x
> top25desk_google_com__hl_en_q_b.skp	17.6us -> 16.4us	0.93x
> keymobi_amazon_com_gp_aw_s_ref_.skp	12.5us -> 11.6us	0.93x
>             keymobi_sfgate_com_.skp	16.6us -> 15.5us	0.93x
> keymobi_booking_com_searchresul.skp	16.2us -> 15.1us	0.93x
>                       tabl_digg.skp	28.8us -> 26.8us	0.93x
>                    tabl_mozilla.skp	80.4us -> 74.6us	0.93x
>                    desk_wowwiki.skp	39.2us -> 36.4us	0.93x
>           top25desk_youtube_com.skp	  42us -> 38.9us	0.93x
>              top25desk_facebook.skp	23.7us ->   22us	0.93x
>               top25desk_blogger.skp	38.2us -> 35.4us	0.93x
> keymobi_online_wsj_com_home_pag.skp	12.8us -> 11.9us	0.93x
>             top25desk_wordpress.skp	28.9us -> 26.8us	0.93x
>     top25desk_answers_yahoo_com.skp	37.2us -> 34.4us	0.93x
> keymobi_plus_google_com_app_bas.skp	9.56us -> 8.85us	0.93x
>               keymobi_wordpress.skp	16.1us -> 14.9us	0.92x
> keymobi_mobile_news_sandbox_goo.skp	27.1us -> 24.9us	0.92x
>        top25desk_techcrunch_com.skp	31.1us -> 28.6us	0.92x
>       keymobi_worldjournal_com_.skp	50.7us -> 46.5us	0.92x
> keymobi_theverge_com_2012_10_28.skp	26.2us ->   24us	0.92x
>             desk_jsfiddlebigcar.skp	1.73us -> 1.59us	0.92x
>           top25desk_weather_com.skp	31.3us -> 28.7us	0.92x
> top25desk_google_com_search_q_c.skp	48.2us -> 44.1us	0.92x
>               top25desk_twitter.skp	27.8us -> 25.5us	0.92x
>               tabl_worldjournal.skp	29.3us -> 26.8us	0.91x
>                    desk_nytimes.skp	  46us ->   42us	0.91x
> top25desk_docs___1_open_documen.skp	6.04us -> 5.51us	0.91x
>       keymobi_wikipedia__1_tab_.skp	59.7us -> 54.4us	0.91x
>               desk_unicodetable.skp	1.12ms -> 1.02ms	0.91x
>              top25desk_ebay_com.skp	17.8us -> 16.2us	0.91x
> keymobi_ftw_usatoday_com_2014_0.skp	26.8us -> 24.3us	0.91x
>     top25desk_sports_yahoo_com_.skp	49.9us -> 45.3us	0.91x
>                 keymobi_cnn_com.skp	9.94us -> 9.03us	0.91x
> keymobi_m_youtube_com_watch_v_9.skp	13.4us -> 12.2us	0.91x
>            top25desk_amazon_com.skp	26.6us -> 24.1us	0.91x
>          keymobi_news_yahoo_com.skp	17.5us -> 15.8us	0.9x
> keymobi_wowwiki_com_world_of_wa.skp	11.2us -> 10.2us	0.9x
> top25desk_plus_google_com_11003.skp	93.5us -> 84.4us	0.9x
>                     desk_carsvg.skp	53.5us -> 48.2us	0.9x
>        top25desk_news_yahoo_com.skp	44.7us -> 40.3us	0.9x
> keymobi_wikipedia__1_tab____del.skp	59.4us -> 53.4us	0.9x
>          desk_googlespreadsheet.skp	  66us -> 59.2us	0.9x
> keymobi_answers_yahoo_com_quest.skp	30.2us ->   27us	0.89x
>              desk_ugamsolutions.skp	  13us -> 11.6us	0.89x
> keymobi_shop_mobileweb_ebay_com.skp	6.96us -> 6.21us	0.89x
>            keymobi_nytimes_com_.skp	12.1us -> 10.8us	0.89x
>                  keymobi_gsp_ro.skp	5.54us -> 4.92us	0.89x
>           top25desk_booking_com.skp	54.9us -> 48.6us	0.89x
>                  top25desk_espn.skp	  37us -> 32.6us	0.88x
> keymobi_facebook_com_barackobam.skp	23.3us -> 20.4us	0.88x
>
> BUG=skia:
> GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2231103002
>
> Committed: https://skia.googlesource.com/skia/+/ac243914af957a806d842318a43dddaf5f941dc3

TBR=mtklein@google.com,mtklein@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review-Url: https://codereview.chromium.org/2232183002
diff --git a/src/core/SkLiteDL.cpp b/src/core/SkLiteDL.cpp
index f847c42..c6a3a8e 100644
--- a/src/core/SkLiteDL.cpp
+++ b/src/core/SkLiteDL.cpp
@@ -59,42 +59,18 @@
 }
 
 namespace {
-#define TYPES(M)                                                                \
-    M(Save) M(Restore) M(SaveLayer)                                             \
-    M(Concat) M(SetMatrix) M(TranslateZ)                                        \
-    M(ClipPath) M(ClipRect) M(ClipRRect) M(ClipRegion)                          \
-    M(DrawPaint) M(DrawPath) M(DrawRect) M(DrawOval) M(DrawRRect) M(DrawDRRect) \
-    M(DrawAnnotation) M(DrawDrawable) M(DrawPicture) M(DrawShadowedPicture)     \
-    M(DrawImage) M(DrawImageNine) M(DrawImageRect) M(DrawImageLattice)          \
-    M(DrawText) M(DrawPosText) M(DrawPosTextH)                                  \
-    M(DrawTextOnPath) M(DrawTextRSXform) M(DrawTextBlob)                        \
-    M(DrawPatch) M(DrawPoints) M(DrawVertices) M(DrawAtlas)
-
-#define M(T) T,
-    enum class Type : uint8_t { TYPES(M) };
-#undef M
-
     struct Op {
-        // These are never called, only used to distinguish Ops that implement
-        // them from those that don't by return type: the real methods return void.
-        int optimizeFor(GrContext*) { sk_throw(); return 0;}
-        int makeThreadsafe()        { sk_throw(); return 0;}
+        virtual ~Op() {}
+        virtual void draw(SkCanvas*) = 0;
+        virtual void optimizeFor(GrContext*) {}
+        virtual void makeThreadsafe() {}
 
-        uint32_t type :  8;
-        uint32_t skip : 24;
+        size_t skip;
     };
-    static_assert(sizeof(Op) == 4, "");
 
-    struct Save final : Op {
-        static const auto kType = Type::Save;
-        void draw(SkCanvas* c) { c->save(); }
-    };
-    struct Restore final : Op {
-        static const auto kType = Type::Restore;
-        void draw(SkCanvas* c) { c->restore(); }
-    };
+    struct Save    final : Op { void draw(SkCanvas* c) override { c->   save(); } };
+    struct Restore final : Op { void draw(SkCanvas* c) override { c->restore(); } };
     struct SaveLayer final : Op {
-        static const auto kType = Type::SaveLayer;
         SaveLayer(const SkRect* bounds, const SkPaint* paint,
                   const SkImageFilter* backdrop, SkCanvas::SaveLayerFlags flags) {
             if (bounds) { this->bounds = *bounds; }
@@ -106,31 +82,28 @@
         SkPaint                    paint;
         sk_sp<const SkImageFilter> backdrop;
         SkCanvas::SaveLayerFlags   flags;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             c->saveLayer({ maybe_unset(bounds), &paint, backdrop.get(), flags });
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
 
     struct Concat final : Op {
-        static const auto kType = Type::Concat;
         Concat(const SkMatrix& matrix) : matrix(matrix) {}
         SkMatrix matrix;
-        void draw(SkCanvas* c) { c->concat(matrix); }
-        void makeThreadsafe() { make_threadsafe(nullptr, &matrix); }
+        void draw(SkCanvas* c) override { c->concat(matrix); }
+        void makeThreadsafe() override { make_threadsafe(nullptr, &matrix); }
     };
     struct SetMatrix final : Op {
-        static const auto kType = Type::SetMatrix;
         SetMatrix(const SkMatrix& matrix) : matrix(matrix) {}
         SkMatrix matrix;
-        void draw(SkCanvas* c) { c->setMatrix(matrix); }
-        void makeThreadsafe() { make_threadsafe(nullptr, &matrix); }
+        void draw(SkCanvas* c) override { c->setMatrix(matrix); }
+        void makeThreadsafe() override { make_threadsafe(nullptr, &matrix); }
     };
     struct TranslateZ final : Op {
-        static const auto kType = Type::TranslateZ;
         TranslateZ(SkScalar dz) : dz(dz) {}
         SkScalar dz;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
         #ifdef SK_EXPERIMENTAL_SHADOWING
             c->translateZ(dz);
         #endif
@@ -138,114 +111,101 @@
     };
 
     struct ClipPath final : Op {
-        static const auto kType = Type::ClipPath;
         ClipPath(const SkPath& path, SkRegion::Op op, bool aa) : path(path), op(op), aa(aa) {}
         SkPath       path;
         SkRegion::Op op;
         bool         aa;
-        void draw(SkCanvas* c) { c->clipPath(path, op, aa); }
-        void makeThreadsafe() { make_threadsafe(&path, nullptr); }
+        void draw(SkCanvas* c) override { c->clipPath(path, op, aa); }
+        void makeThreadsafe() override { make_threadsafe(&path, nullptr); }
     };
     struct ClipRect final : Op {
-        static const auto kType = Type::ClipRect;
         ClipRect(const SkRect& rect, SkRegion::Op op, bool aa) : rect(rect), op(op), aa(aa) {}
         SkRect       rect;
         SkRegion::Op op;
         bool         aa;
-        void draw(SkCanvas* c) { c->clipRect(rect, op, aa); }
+        void draw(SkCanvas* c) override { c->clipRect(rect, op, aa); }
     };
     struct ClipRRect final : Op {
-        static const auto kType = Type::ClipRRect;
         ClipRRect(const SkRRect& rrect, SkRegion::Op op, bool aa) : rrect(rrect), op(op), aa(aa) {}
         SkRRect      rrect;
         SkRegion::Op op;
         bool         aa;
-        void draw(SkCanvas* c) { c->clipRRect(rrect, op, aa); }
+        void draw(SkCanvas* c) override { c->clipRRect(rrect, op, aa); }
     };
     struct ClipRegion final : Op {
-        static const auto kType = Type::ClipRegion;
         ClipRegion(const SkRegion& region, SkRegion::Op op) : region(region), op(op) {}
         SkRegion     region;
         SkRegion::Op op;
-        void draw(SkCanvas* c) { c->clipRegion(region, op); }
+        void draw(SkCanvas* c) override { c->clipRegion(region, op); }
     };
 
     struct DrawPaint final : Op {
-        static const auto kType = Type::DrawPaint;
         DrawPaint(const SkPaint& paint) : paint(paint) {}
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawPaint(paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawPaint(paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawPath final : Op {
-        static const auto kType = Type::DrawPath;
         DrawPath(const SkPath& path, const SkPaint& paint) : path(path), paint(paint) {}
         SkPath  path;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawPath(path, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
-        void makeThreadsafe() { make_threadsafe(&path, nullptr); }
+        void draw(SkCanvas* c) override { c->drawPath(path, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
+        void makeThreadsafe() override { make_threadsafe(&path, nullptr); }
     };
     struct DrawRect final : Op {
-        static const auto kType = Type::DrawRect;
         DrawRect(const SkRect& rect, const SkPaint& paint) : rect(rect), paint(paint) {}
         SkRect  rect;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawRect(rect, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawRect(rect, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawOval final : Op {
-        static const auto kType = Type::DrawOval;
         DrawOval(const SkRect& oval, const SkPaint& paint) : oval(oval), paint(paint) {}
         SkRect  oval;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawOval(oval, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawOval(oval, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawRRect final : Op {
-        static const auto kType = Type::DrawRRect;
         DrawRRect(const SkRRect& rrect, const SkPaint& paint) : rrect(rrect), paint(paint) {}
         SkRRect rrect;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawRRect(rrect, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawRRect(rrect, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawDRRect final : Op {
-        static const auto kType = Type::DrawDRRect;
         DrawDRRect(const SkRRect& outer, const SkRRect& inner, const SkPaint& paint)
             : outer(outer), inner(inner), paint(paint) {}
         SkRRect outer, inner;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawDRRect(outer, inner, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawDRRect(outer, inner, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
 
     struct DrawAnnotation final : Op {
-        static const auto kType = Type::DrawAnnotation;
         DrawAnnotation(const SkRect& rect, SkData* value) : rect(rect), value(sk_ref_sp(value)) {}
         SkRect        rect;
         sk_sp<SkData> value;
-        void draw(SkCanvas* c) { c->drawAnnotation(rect, pod<char>(this), value.get()); }
+        void draw(SkCanvas* c) override { c->drawAnnotation(rect, pod<char>(this), value.get()); }
     };
     struct DrawDrawable final : Op {
-        static const auto kType = Type::DrawDrawable;
         DrawDrawable(SkDrawable* drawable, const SkMatrix* matrix) : drawable(sk_ref_sp(drawable)) {
             if (matrix) { this->matrix = *matrix; }
         }
         sk_sp<SkDrawable>      drawable;
         sk_sp<const SkPicture> snapped;
         SkMatrix               matrix = SkMatrix::I();
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             snapped ? c->drawPicture(snapped.get(), &matrix, nullptr)
                     : c->drawDrawable(drawable.get(), &matrix);
         }
-        void makeThreadsafe() {
+        void makeThreadsafe() override {
             snapped.reset(drawable->newPictureSnapshot());
             make_threadsafe(nullptr, &matrix);
         }
     };
     struct DrawPicture final : Op {
-        static const auto kType = Type::DrawPicture;
         DrawPicture(const SkPicture* picture, const SkMatrix* matrix, const SkPaint* paint)
             : picture(sk_ref_sp(picture)) {
             if (matrix) { this->matrix = *matrix; }
@@ -255,14 +215,13 @@
         SkMatrix               matrix = SkMatrix::I();
         SkPaint                paint;
         bool                   has_paint = false;  // TODO: why is a default paint not the same?
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             c->drawPicture(picture.get(), &matrix, has_paint ? &paint : nullptr);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
-        void makeThreadsafe() { make_threadsafe(nullptr, &matrix); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
+        void makeThreadsafe() override { make_threadsafe(nullptr, &matrix); }
     };
     struct DrawShadowedPicture final : Op {
-        static const auto kType = Type::DrawShadowedPicture;
         DrawShadowedPicture(const SkPicture* picture, const SkMatrix* matrix, const SkPaint* paint)
             : picture(sk_ref_sp(picture)) {
             if (matrix) { this->matrix = *matrix; }
@@ -271,17 +230,16 @@
         sk_sp<const SkPicture> picture;
         SkMatrix               matrix = SkMatrix::I();
         SkPaint                paint;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
         #ifdef SK_EXPERIMENTAL_SHADOWING
             c->drawShadowedPicture(picture.get(), &matrix, &paint);
         #endif
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
-        void makeThreadsafe() { make_threadsafe(nullptr, &matrix); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
+        void makeThreadsafe() override { make_threadsafe(nullptr, &matrix); }
     };
 
     struct DrawImage final : Op {
-        static const auto kType = Type::DrawImage;
         DrawImage(sk_sp<const SkImage>&& image, SkScalar x, SkScalar y, const SkPaint* paint)
             : image(std::move(image)), x(x), y(y) {
             if (paint) { this->paint = *paint; }
@@ -289,11 +247,10 @@
         sk_sp<const SkImage> image;
         SkScalar x,y;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawImage(image.get(), x,y, &paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint, &image); }
+        void draw(SkCanvas* c) override { c->drawImage(image.get(), x,y, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint, &image); }
     };
     struct DrawImageNine final : Op {
-        static const auto kType = Type::DrawImageNine;
         DrawImageNine(sk_sp<const SkImage>&& image,
                       const SkIRect& center, const SkRect& dst, const SkPaint* paint)
             : image(std::move(image)), center(center), dst(dst) {
@@ -303,11 +260,10 @@
         SkIRect center;
         SkRect  dst;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawImageNine(image.get(), center, dst, &paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint, &image); }
+        void draw(SkCanvas* c) override { c->drawImageNine(image.get(), center, dst, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint, &image); }
     };
     struct DrawImageRect final : Op {
-        static const auto kType = Type::DrawImageRect;
         DrawImageRect(sk_sp<const SkImage>&& image, const SkRect* src, const SkRect& dst,
                       const SkPaint* paint, SkCanvas::SrcRectConstraint constraint)
             : image(std::move(image)), dst(dst), constraint(constraint) {
@@ -318,13 +274,12 @@
         SkRect src, dst;
         SkPaint paint;
         SkCanvas::SrcRectConstraint constraint;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             c->drawImageRect(image.get(), src, dst, &paint, constraint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint, &image); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint, &image); }
     };
     struct DrawImageLattice final : Op {
-        static const auto kType = Type::DrawImageLattice;
         DrawImageLattice(sk_sp<const SkImage>&& image, int xs, int ys,
                          const SkRect& dst, const SkPaint* paint)
             : image(std::move(image)), xs(xs), ys(ys), dst(dst) {
@@ -334,55 +289,51 @@
         int                  xs, ys;
         SkRect               dst;
         SkPaint              paint;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             auto xdivs = pod<int>(this, 0),
                  ydivs = pod<int>(this, xs*sizeof(int));
             c->drawImageLattice(image.get(), {xdivs, xs, ydivs, ys}, dst, &paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint, &image); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint, &image); }
     };
 
     struct DrawText final : Op {
-        static const auto kType = Type::DrawText;
         DrawText(size_t bytes, SkScalar x, SkScalar y, const SkPaint& paint)
             : bytes(bytes), x(x), y(y), paint(paint) {}
         size_t bytes;
         SkScalar x,y;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawText(pod<void>(this), bytes, x,y, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawText(pod<void>(this), bytes, x,y, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawPosText final : Op {
-        static const auto kType = Type::DrawPosText;
         DrawPosText(size_t bytes, const SkPaint& paint, int n)
             : bytes(bytes), paint(paint), n(n) {}
         size_t bytes;
         SkPaint paint;
         int n;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             auto points = pod<SkPoint>(this);
             auto text   = pod<void>(this, n*sizeof(SkPoint));
             c->drawPosText(text, bytes, points, paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawPosTextH final : Op {
-        static const auto kType = Type::DrawPosTextH;
         DrawPosTextH(size_t bytes, SkScalar y, const SkPaint& paint, int n)
             : bytes(bytes), y(y), paint(paint), n(n) {}
         size_t   bytes;
         SkScalar y;
         SkPaint  paint;
         int n;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             auto xs   = pod<SkScalar>(this);
             auto text = pod<void>(this, n*sizeof(SkScalar));
             c->drawPosTextH(text, bytes, xs, y, paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawTextOnPath final : Op {
-        static const auto kType = Type::DrawTextOnPath;
         DrawTextOnPath(size_t bytes, const SkPath& path,
                        const SkMatrix* matrix, const SkPaint& paint)
             : bytes(bytes), path(path), paint(paint) {
@@ -392,14 +343,13 @@
         SkPath   path;
         SkMatrix matrix = SkMatrix::I();
         SkPaint  paint;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             c->drawTextOnPath(pod<void>(this), bytes, path, &matrix, paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
-        void makeThreadsafe() { make_threadsafe(&path, &matrix); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
+        void makeThreadsafe() override { make_threadsafe(&path, &matrix); }
     };
     struct DrawTextRSXform final : Op {
-        static const auto kType = Type::DrawTextRSXform;
         DrawTextRSXform(size_t bytes, const SkRect* cull, const SkPaint& paint)
             : bytes(bytes), paint(paint) {
             if (cull) { this->cull = *cull; }
@@ -407,25 +357,23 @@
         size_t  bytes;
         SkRect  cull = kUnset;
         SkPaint paint;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             c->drawTextRSXform(pod<void>(this), bytes, pod<SkRSXform>(this, bytes),
                                maybe_unset(cull), paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawTextBlob final : Op {
-        static const auto kType = Type::DrawTextBlob;
         DrawTextBlob(const SkTextBlob* blob, SkScalar x, SkScalar y, const SkPaint& paint)
             : blob(sk_ref_sp(blob)), x(x), y(y), paint(paint) {}
         sk_sp<const SkTextBlob> blob;
         SkScalar x,y;
         SkPaint paint;
-        void draw(SkCanvas* c) { c->drawTextBlob(blob.get(), x,y, paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawTextBlob(blob.get(), x,y, paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
 
     struct DrawPatch final : Op {
-        static const auto kType = Type::DrawPatch;
         DrawPatch(const SkPoint cubics[12], const SkColor colors[4], const SkPoint texs[4],
                   SkXfermode* xfermode, const SkPaint& paint)
             : xfermode(sk_ref_sp(xfermode)), paint(paint) {
@@ -440,24 +388,22 @@
         SkPaint           paint;
         bool              has_colors = false;
         bool              has_texs   = false;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             c->drawPatch(cubics, has_colors ? colors : nullptr, has_texs ? texs : nullptr,
                          xfermode.get(), paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawPoints final : Op {
-        static const auto kType = Type::DrawPoints;
         DrawPoints(SkCanvas::PointMode mode, size_t count, const SkPaint& paint)
             : mode(mode), count(count), paint(paint) {}
         SkCanvas::PointMode mode;
         size_t              count;
         SkPaint             paint;
-        void draw(SkCanvas* c) { c->drawPoints(mode, count, pod<SkPoint>(this), paint); }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void draw(SkCanvas* c) override { c->drawPoints(mode, count, pod<SkPoint>(this), paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawVertices final : Op {
-        static const auto kType = Type::DrawVertices;
         DrawVertices(SkCanvas::VertexMode mode, int count, SkXfermode* xfermode, int nindices,
                      const SkPaint& paint, bool has_texs, bool has_colors, bool has_indices)
             : mode(mode), count(count), xfermode(sk_ref_sp(xfermode)), nindices(nindices)
@@ -470,7 +416,7 @@
         bool                 has_texs;
         bool                 has_colors;
         bool                 has_indices;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             SkPoint* vertices = pod<SkPoint>(this, 0);
             size_t offset = count*sizeof(SkPoint);
 
@@ -493,10 +439,9 @@
             c->drawVertices(mode, count, vertices, texs, colors, xfermode.get(),
                             indices, nindices, paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint); }
     };
     struct DrawAtlas final : Op {
-        static const auto kType = Type::DrawAtlas;
         DrawAtlas(const SkImage* atlas, int count, SkXfermode::Mode xfermode,
                   const SkRect* cull, const SkPaint* paint, bool has_colors)
             : atlas(sk_ref_sp(atlas)), count(count), xfermode(xfermode), has_colors(has_colors) {
@@ -509,7 +454,7 @@
         SkRect               cull = kUnset;
         SkPaint              paint;
         bool                 has_colors;
-        void draw(SkCanvas* c) {
+        void draw(SkCanvas* c) override {
             auto xforms = pod<SkRSXform>(this, 0);
             auto   texs = pod<SkRect>(this, count*sizeof(SkRSXform));
             auto colors = has_colors
@@ -518,14 +463,13 @@
             c->drawAtlas(atlas.get(), xforms, texs, colors, count, xfermode,
                          maybe_unset(cull), &paint);
         }
-        void optimizeFor(GrContext* ctx) { optimize_for(ctx, &paint, &atlas); }
+        void optimizeFor(GrContext* ctx) override { optimize_for(ctx, &paint, &atlas); }
     };
 }
 
 template <typename T, typename... Args>
 void* SkLiteDL::push(size_t pod, Args&&... args) {
     size_t skip = SkAlignPtr(sizeof(T) + pod);
-    SkASSERT(skip < (1<<24));
     if (fUsed + skip > fReserved) {
         fReserved = (fUsed + skip + 4096) & ~4095;  // Next greater multiple of 4096.
         fBytes.realloc(fReserved);
@@ -534,22 +478,17 @@
     auto op = (T*)(fBytes.get() + fUsed);
     fUsed += skip;
     new (op) T{ std::forward<Args>(args)... };
-    op->type = (uint32_t)T::kType;
     op->skip = skip;
     return op+1;
 }
 
-template <typename... Args>
-inline void SkLiteDL::map(void (*const fns[])(void*, Args...), Args... args) {
+template <typename Fn>
+void SkLiteDL::map(Fn&& fn) {
     auto end = fBytes.get() + fUsed;
     for (uint8_t* ptr = fBytes.get(); ptr < end; ) {
         auto op = (Op*)ptr;
-        auto type = op->type;
-        auto skip = op->skip;
-        if (auto fn = fns[type]) {  // We replace no-op functions with nullptrs
-            fn(op, args...);        // to avoid the overhead of a pointless call.
-        }
-        ptr += skip;
+        fn(op);
+        ptr += op->skip;
     }
 }
 
@@ -714,36 +653,18 @@
                 colors, colors ? count : 0);
 }
 
-typedef void(* skcanvas_fn)(void*,  SkCanvas*);
-typedef void(*grcontext_fn)(void*, GrContext*);
-typedef void(*     void_fn)(void*);
 
-// All ops implement draw().
-#define M(T) [](void* op, SkCanvas* c) { ((T*)op)->draw(c); },
-static const skcanvas_fn draw_fns[] = { TYPES(M) };
-#undef M
+void SkLiteDL::onDraw(SkCanvas* canvas) {
+    this->map([canvas](Op* op) { op->draw(canvas); });
+}
 
-// Ops that implement optimizeFor() or makeThreadsafe() return void from those functions;
-// the (throwing) defaults return int.
-#define M(T) std::is_void<decltype(((T*)nullptr)->optimizeFor(nullptr))>::value \
-    ? [](void* op, GrContext* ctx) { ((T*)op)->optimizeFor(ctx); } : (grcontext_fn)nullptr,
-static const grcontext_fn optimize_for_fns[] = { TYPES(M) };
-#undef M
+void SkLiteDL::optimizeFor(GrContext* ctx) {
+    this->map([ctx](Op* op) { op->optimizeFor(ctx); });
+}
 
-#define M(T) std::is_void<decltype(((T*)nullptr)->makeThreadsafe())>::value \
-    ? [](void* op) { ((T*)op)->makeThreadsafe(); } : (void_fn)nullptr,
-static const void_fn make_threadsafe_fns[] = { TYPES(M) };
-#undef M
-
-// Most state ops (matrix, clip, save, restore) have a trivial destructor.
-#define M(T) !std::is_trivially_destructible<T>::value \
-    ? [](void* op) { ((T*)op)->~T(); } : (void_fn)nullptr,
-static const void_fn dtor_fns[] = { TYPES(M) };
-#undef M
-
-void SkLiteDL::onDraw        (SkCanvas* canvas) { this->map(draw_fns, canvas); }
-void SkLiteDL::optimizeFor   (GrContext* ctx)   { this->map(optimize_for_fns, ctx); }
-void SkLiteDL::makeThreadsafe()                 { this->map(make_threadsafe_fns); }
+void SkLiteDL::makeThreadsafe() {
+    this->map([](Op* op) { op->makeThreadsafe(); });
+}
 
 SkRect SkLiteDL::onGetBounds() {
     return fBounds;
@@ -784,7 +705,7 @@
     this->internal_dispose_restore_refcnt_to_1();
 
     auto self = const_cast<SkLiteDL*>(this);
-    self->map(dtor_fns);
+    self->map([](Op* op) { op->~Op(); });
 
     if (--self->fUsesRemaining > 0) {
         self->fUsed = 0;
diff --git a/src/core/SkLiteDL.h b/src/core/SkLiteDL.h
index 0798366..27e3f27 100644
--- a/src/core/SkLiteDL.h
+++ b/src/core/SkLiteDL.h
@@ -89,8 +89,8 @@
     template <typename T, typename... Args>
     void* push(size_t, Args&&...);
 
-    template <typename... Args>
-    void map(void (*const [])(void*, Args...), Args...);
+    template <typename Fn>
+    void map(Fn&& fn);
 
     SkAutoTMalloc<uint8_t> fBytes;
     size_t                 fUsed;