Revert of Revert of Change device creation to see the (optional) layer-paint (patchset #1 id:1 of https://codereview.chromium.org/1008863002/)

Reason for revert:
guard in chrome has landed

Original issue's description:
> Revert of Change device creation to see the (optional) layer-paint (patchset #9 id:160001 of https://codereview.chromium.org/988413003/)
>
> Reason for revert:
> need to have chrome opt-in for the older API before this can land (in chrome)
>
> Original issue's description:
> > Change device creation to see the (optional) layer-paint
> >
> > Motivation:
> >
> > PDFDevice currently relies on 1) being told that the layer's paint has an imagefilter, and in the case, it creates a rasterdevice. It then relies on (2) canvas itself sniffing the layer's paint and offering to apply-the-imagefilter to call drawSprite instead of drawDevice.
> >
> > This subtle interchange is fragile, and also does not support other unsupported PDF features like colorfilters. This CL is a step toward making this use-raster-instead-of-native approach to layers more completely in the subclass' hands.
> >
> > Committed: https://skia.googlesource.com/skia/+/1182d9a96b80bd12183ee7c81325a979a51ee0c0
>
> TBR=halcanary@google.com,senorblanco@google.com,robertphillips@google.com
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://skia.googlesource.com/skia/+/0e040f7da2fdfeb49aa60d24117306e3b1e6ea90

TBR=halcanary@google.com,senorblanco@google.com,robertphillips@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1006923002
diff --git a/include/core/SkBitmapDevice.h b/include/core/SkBitmapDevice.h
index 8ca6a52..caff685 100644
--- a/include/core/SkBitmapDevice.h
+++ b/include/core/SkBitmapDevice.h
@@ -98,11 +98,7 @@
                               const SkColor colors[], SkXfermode* xmode,
                               const uint16_t indices[], int indexCount,
                               const SkPaint& paint) SK_OVERRIDE;
-    /** The SkBaseDevice passed will be an SkBaseDevice which was returned by a call to
-        onCreateCompatibleDevice on this device with kSaveLayer_Usage.
-     */
-    virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
-                            const SkPaint&) SK_OVERRIDE;
+    virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y, const SkPaint&) SK_OVERRIDE;
 
     ///////////////////////////////////////////////////////////////////////////
 
@@ -145,7 +141,7 @@
     // any clip information.
     void replaceBitmapBackendForRasterSurface(const SkBitmap&) SK_OVERRIDE;
 
-    SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) SK_OVERRIDE;
+    SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) SK_OVERRIDE;
 
     SkSurface* newSurface(const SkImageInfo&, const SkSurfaceProps&) SK_OVERRIDE;
     const void* peekPixels(SkImageInfo*, size_t* rowBytes) SK_OVERRIDE;
diff --git a/include/core/SkCanvas.h b/include/core/SkCanvas.h
index 74bf909c..836f7b1 100644
--- a/include/core/SkCanvas.h
+++ b/include/core/SkCanvas.h
@@ -1321,8 +1321,7 @@
     void internalDrawBitmapNine(const SkBitmap& bitmap, const SkIRect& center,
                                 const SkRect& dst, const SkPaint* paint);
     void internalDrawPaint(const SkPaint& paint);
-    void internalSaveLayer(const SkRect* bounds, const SkPaint* paint,
-                           SaveFlags, bool justForImageFilter, SaveLayerStrategy strategy);
+    void internalSaveLayer(const SkRect* bounds, const SkPaint*, SaveFlags, SaveLayerStrategy);
     void internalDrawDevice(SkBaseDevice*, int x, int y, const SkPaint*);
 
     // shared by save() and saveLayer()
diff --git a/include/core/SkDevice.h b/include/core/SkDevice.h
index c7c5c30..684a084 100644
--- a/include/core/SkDevice.h
+++ b/include/core/SkDevice.h
@@ -125,10 +125,9 @@
     };
 
 protected:
-    enum Usage {
-       kGeneral_Usage,
-       kSaveLayer_Usage,  // <! internal use only
-       kImageFilter_Usage // <! internal use only
+    enum TileUsage {
+        kPossible_TileUsage,    //!< the created device may be drawn tiled
+        kNever_TileUsage,       //!< the created device will never be drawn tiled
     };
 
     struct TextFlags {
@@ -231,7 +230,7 @@
     virtual void drawPatch(const SkDraw&, const SkPoint cubics[12], const SkColor colors[4],
                            const SkPoint texCoords[4], SkXfermode* xmode, const SkPaint& paint);
     /** The SkDevice passed will be an SkDevice which was returned by a call to
-        onCreateCompatibleDevice on this device with kSaveLayer_Usage.
+        onCreateDevice on this device with kNeverTile_TileExpectation.
      */
     virtual void drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
                             const SkPaint&) = 0;
@@ -255,14 +254,6 @@
     virtual void unlockPixels() {}
 
     /**
-     *  Returns true if the device allows processing of this imagefilter. If
-     *  false is returned, then the filter is ignored. This may happen for
-     *  some subclasses that do not support pixel manipulations after drawing
-     *  has occurred (e.g. printing). The default implementation returns true.
-     */
-    virtual bool allowImageFilter(const SkImageFilter*) { return true; }
-
-    /**
      *  Override and return true for filters that the device can handle
      *  intrinsically. Doing so means that SkCanvas will pass-through this
      *  filter to drawSprite and drawDevice (and potentially filterImage).
@@ -336,24 +327,39 @@
                                           const SkPaint*);
 
     struct CreateInfo {
-        static SkPixelGeometry AdjustGeometry(const SkImageInfo&, Usage, SkPixelGeometry geo);
+        static SkPixelGeometry AdjustGeometry(const SkImageInfo&, TileUsage, SkPixelGeometry);
 
-        // The construct may change the pixel geometry based on usage as needed.
-        CreateInfo(const SkImageInfo& info, Usage usage, SkPixelGeometry geo)
+        // The constructor may change the pixel geometry based on other parameters.
+        CreateInfo(const SkImageInfo& info, TileUsage tileUsage, SkPixelGeometry geo)
             : fInfo(info)
-            , fUsage(usage)
-            , fPixelGeometry(AdjustGeometry(info, usage, geo))
+            , fTileUsage(tileUsage)
+            , fPixelGeometry(AdjustGeometry(info, tileUsage, geo))
         {}
 
-        const SkImageInfo     fInfo;
-        const Usage           fUsage;
-        const SkPixelGeometry fPixelGeometry;
+        const SkImageInfo       fInfo;
+        const TileUsage         fTileUsage;
+        const SkPixelGeometry   fPixelGeometry;
     };
 
+#ifdef SK_SUPPORT_LEGACY_ONCREATECOMPATIBLEDEVICE
+    // legacy method name -- please override onCreateDevice instead
     virtual SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) {
         return NULL;
     }
 
+    virtual SkBaseDevice* onCreateDevice(const CreateInfo& cinfo, const SkPaint* layerPaint) {
+        return this->onCreateCompatibleDevice(cinfo);
+    }
+#else
+    /**
+     *  Create a new device based on CreateInfo. If the paint is not null, then it represents a
+     *  preview of how the new device will be composed with its creator device (this).
+     */
+    virtual SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) {
+        return NULL;
+    }
+#endif
+
     virtual void initForRootLayer(SkPixelGeometry geo);
 
 private:
diff --git a/include/device/xps/SkXPSDevice.h b/include/device/xps/SkXPSDevice.h
index 514259d..10dab81 100644
--- a/include/device/xps/SkXPSDevice.h
+++ b/include/device/xps/SkXPSDevice.h
@@ -135,8 +135,6 @@
         int x, int y,
         const SkPaint& paint) SK_OVERRIDE;
 
-    bool allowImageFilter(const SkImageFilter*) SK_OVERRIDE;
-
 private:
     class TypefaceUse : ::SkNoncopyable {
     public:
@@ -311,7 +309,7 @@
         const SkVector& ppuScale,
         IXpsOMPath* shadedPath);
 
-    SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) SK_OVERRIDE;
+    SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) SK_OVERRIDE;
 
     // Disable the default copy and assign implementation.
     SkXPSDevice(const SkXPSDevice&);
diff --git a/src/core/SkBitmapDevice.cpp b/src/core/SkBitmapDevice.cpp
index 37cbff5..5fae2b5 100644
--- a/src/core/SkBitmapDevice.cpp
+++ b/src/core/SkBitmapDevice.cpp
@@ -110,7 +110,7 @@
     fBitmap.lockPixels();
 }
 
-SkBaseDevice* SkBitmapDevice::onCreateCompatibleDevice(const CreateInfo& cinfo) {
+SkBaseDevice* SkBitmapDevice::onCreateDevice(const CreateInfo& cinfo, const SkPaint*) {
     SkDeviceProperties leaky(cinfo.fPixelGeometry);
     return SkBitmapDevice::Create(cinfo.fInfo, &leaky);
 }
diff --git a/src/core/SkCanvas.cpp b/src/core/SkCanvas.cpp
index a31ded0..11dc739 100644
--- a/src/core/SkCanvas.cpp
+++ b/src/core/SkCanvas.cpp
@@ -299,7 +299,7 @@
             SkPaint tmp;
             tmp.setImageFilter(fOrigPaint.getImageFilter());
             (void)canvas->internalSaveLayer(bounds, &tmp, SkCanvas::kARGB_ClipLayer_SaveFlag,
-                                            true, SkCanvas::kFullLayer_SaveLayerStrategy);
+                                            SkCanvas::kFullLayer_SaveLayerStrategy);
             // we'll clear the imageFilter for the actual draws in next(), so
             // it will only be applied during the restore().
             fDoClearImageFilter = true;
@@ -880,7 +880,7 @@
     }
     SaveLayerStrategy strategy = this->willSaveLayer(bounds, paint, kARGB_ClipLayer_SaveFlag);
     fSaveCount += 1;
-    this->internalSaveLayer(bounds, paint, kARGB_ClipLayer_SaveFlag, false, strategy);
+    this->internalSaveLayer(bounds, paint, kARGB_ClipLayer_SaveFlag, strategy);
     return this->getSaveCount() - 1;
 }
 
@@ -890,12 +890,12 @@
     }
     SaveLayerStrategy strategy = this->willSaveLayer(bounds, paint, flags);
     fSaveCount += 1;
-    this->internalSaveLayer(bounds, paint, flags, false, strategy);
+    this->internalSaveLayer(bounds, paint, flags, strategy);
     return this->getSaveCount() - 1;
 }
 
 void SkCanvas::internalSaveLayer(const SkRect* bounds, const SkPaint* paint, SaveFlags flags,
-                                bool justForImageFilter, SaveLayerStrategy strategy) {
+                                 SaveLayerStrategy strategy) {
 #ifndef SK_SUPPORT_LEGACY_CLIPTOLAYERFLAG
     flags |= kClipToLayer_SaveFlag;
 #endif
@@ -917,21 +917,13 @@
         return;
     }
 
-    // Kill the imagefilter if our device doesn't allow it
-    SkLazyPaint lazyP;
-    if (paint && paint->getImageFilter()) {
-        if (!this->getTopDevice()->allowImageFilter(paint->getImageFilter())) {
-            if (justForImageFilter) {
-                // early exit if the layer was just for the imageFilter
-                return;
-            }
-            SkPaint* p = lazyP.set(*paint);
-            p->setImageFilter(NULL);
-            paint = p;
+    bool isOpaque = !SkToBool(flags & kHasAlphaLayer_SaveFlag);
+    if (isOpaque && paint) {
+        // TODO: perhaps add a query to filters so we might preserve opaqueness...
+        if (paint->getImageFilter() || paint->getColorFilter()) {
+            isOpaque = false;
         }
     }
-
-    bool isOpaque = !SkToBool(flags & kHasAlphaLayer_SaveFlag);
     SkImageInfo info = SkImageInfo::MakeN32(ir.width(), ir.height(),
                         isOpaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType);
 
@@ -941,12 +933,17 @@
         return;
     }
 
-    SkBaseDevice::Usage usage = SkBaseDevice::kSaveLayer_Usage;
+    SkBaseDevice::TileUsage usage = SkBaseDevice::kNever_TileUsage;
+#if 1
+    // this seems needed for current GMs, but makes us draw slower on the GPU
+    // Related to https://code.google.com/p/skia/issues/detail?id=3519 ?
+    //
     if (paint && paint->getImageFilter()) {
-        usage = SkBaseDevice::kImageFilter_Usage;
+        usage = SkBaseDevice::kPossible_TileUsage;
     }
-    device = device->onCreateCompatibleDevice(SkBaseDevice::CreateInfo(info, usage,
-                                                                       fProps.pixelGeometry()));
+#endif
+    device = device->onCreateDevice(SkBaseDevice::CreateInfo(info, usage, fProps.pixelGeometry()),
+                                    paint);
     if (NULL == device) {
         SkErrorInternals::SetError( kInternalError_SkError,
                                     "Unable to create device for layer.");
diff --git a/src/core/SkDevice.cpp b/src/core/SkDevice.cpp
index a77e54c..d76a180 100644
--- a/src/core/SkDevice.cpp
+++ b/src/core/SkDevice.cpp
@@ -64,19 +64,16 @@
 }
 
 SkPixelGeometry SkBaseDevice::CreateInfo::AdjustGeometry(const SkImageInfo& info,
-                                                         Usage usage,
+                                                         TileUsage tileUsage,
                                                          SkPixelGeometry geo) {
-    switch (usage) {
-        case kGeneral_Usage:
+    switch (tileUsage) {
+        case kPossible_TileUsage:
             break;
-        case kSaveLayer_Usage:
+        case kNever_TileUsage:
             if (info.alphaType() != kOpaque_SkAlphaType) {
                 geo = kUnknown_SkPixelGeometry;
             }
             break;
-        case kImageFilter_Usage:
-            geo = kUnknown_SkPixelGeometry;
-            break;
     }
     return geo;
 }
@@ -86,7 +83,7 @@
     // anyway to document logically what is going on.
     //
     fLeakyProperties->setPixelGeometry(CreateInfo::AdjustGeometry(this->imageInfo(),
-                                                                  kGeneral_Usage,
+                                                                  kPossible_TileUsage,
                                                                   geo));
 }
 
diff --git a/src/core/SkDeviceImageFilterProxy.h b/src/core/SkDeviceImageFilterProxy.h
index 0ae686d..11a95ff 100644
--- a/src/core/SkDeviceImageFilterProxy.h
+++ b/src/core/SkDeviceImageFilterProxy.h
@@ -18,15 +18,15 @@
         : fDevice(device)
         , fProps(props.flags(),
                  SkBaseDevice::CreateInfo::AdjustGeometry(SkImageInfo(),
-                                                          SkBaseDevice::kImageFilter_Usage,
+                                                          SkBaseDevice::kPossible_TileUsage,
                                                           props.pixelGeometry()))
     {}
 
     SkBaseDevice* createDevice(int w, int h) SK_OVERRIDE {
         SkBaseDevice::CreateInfo cinfo(SkImageInfo::MakeN32Premul(w, h),
-                                       SkBaseDevice::kImageFilter_Usage,
+                                       SkBaseDevice::kPossible_TileUsage,
                                        kUnknown_SkPixelGeometry);
-        return fDevice->onCreateCompatibleDevice(cinfo);
+        return fDevice->onCreateDevice(cinfo, NULL);
     }
     bool canHandleImageFilter(const SkImageFilter* filter) SK_OVERRIDE {
         return fDevice->canHandleImageFilter(filter);
diff --git a/src/device/xps/SkXPSDevice.cpp b/src/device/xps/SkXPSDevice.cpp
index 2ca799a..88d1182 100644
--- a/src/device/xps/SkXPSDevice.cpp
+++ b/src/device/xps/SkXPSDevice.cpp
@@ -2251,7 +2251,7 @@
          "Could not add layer to current visuals.");
 }
 
-SkBaseDevice* SkXPSDevice::onCreateCompatibleDevice(const CreateInfo& info) {
+SkBaseDevice* SkXPSDevice::onCreateDevice(const CreateInfo& info, const SkPaint*) {
 //Conditional for bug compatibility with PDF device.
 #if 0
     if (SkBaseDevice::kGeneral_Usage == info.fUsage) {
@@ -2282,6 +2282,3 @@
          "Could not create canvas for layer.");
 }
 
-bool SkXPSDevice::allowImageFilter(const SkImageFilter*) {
-    return false;
-}
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index fb5fa7c..757dfbf 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -1862,7 +1862,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-SkBaseDevice* SkGpuDevice::onCreateCompatibleDevice(const CreateInfo& cinfo) {
+SkBaseDevice* SkGpuDevice::onCreateDevice(const CreateInfo& cinfo, const SkPaint*) {
     GrSurfaceDesc desc;
     desc.fConfig = fRenderTarget->config();
     desc.fFlags = kRenderTarget_GrSurfaceFlag;
@@ -1876,7 +1876,7 @@
 
     // layers are never draw in repeat modes, so we can request an approx
     // match and ignore any padding.
-    const GrContext::ScratchTexMatch match = (kSaveLayer_Usage == cinfo.fUsage) ?
+    const GrContext::ScratchTexMatch match = (kNever_TileUsage == cinfo.fTileUsage) ?
                                                 GrContext::kApprox_ScratchTexMatch :
                                                 GrContext::kExact_ScratchTexMatch;
     texture.reset(fContext->refScratchTexture(desc, match));
diff --git a/src/gpu/SkGpuDevice.h b/src/gpu/SkGpuDevice.h
index 6b520e7..50aa586 100644
--- a/src/gpu/SkGpuDevice.h
+++ b/src/gpu/SkGpuDevice.h
@@ -51,9 +51,9 @@
     virtual ~SkGpuDevice();
 
     SkGpuDevice* cloneDevice(const SkSurfaceProps& props) {
-        SkBaseDevice* dev = this->onCreateCompatibleDevice(CreateInfo(this->imageInfo(),
-                                                                      kGeneral_Usage,
-                                                                      props.pixelGeometry()));
+        SkBaseDevice* dev = this->onCreateDevice(CreateInfo(this->imageInfo(), kPossible_TileUsage,
+                                                            props.pixelGeometry()),
+                                                 NULL);
         return static_cast<SkGpuDevice*>(dev);
     }
 
@@ -147,7 +147,7 @@
 
     SkGpuDevice(GrRenderTarget*, const SkSurfaceProps*, unsigned flags);
 
-    SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) SK_OVERRIDE;
+    SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) SK_OVERRIDE;
 
     SkSurface* newSurface(const SkImageInfo&, const SkSurfaceProps&) SK_OVERRIDE;
 
diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index 99f3ce1..273b958 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -566,13 +566,19 @@
     }
 }
 
-SkBaseDevice* SkPDFDevice::onCreateCompatibleDevice(const CreateInfo& cinfo) {
+static bool not_supported_for_layers(const SkPaint& layerPaint) {
     // PDF does not support image filters, so render them on CPU.
     // Note that this rendering is done at "screen" resolution (100dpi), not
     // printer resolution.
     // FIXME: It may be possible to express some filters natively using PDF
     // to improve quality and file size (http://skbug.com/3043)
-    if (kImageFilter_Usage == cinfo.fUsage) {
+
+    // TODO: should we return true if there is a colorfilter?
+    return layerPaint.getImageFilter() != NULL;
+}
+
+SkBaseDevice* SkPDFDevice::onCreateDevice(const CreateInfo& cinfo, const SkPaint* layerPaint) {
+    if (layerPaint && not_supported_for_layers(*layerPaint)) {
         return SkBitmapDevice::Create(cinfo.fInfo);
     }
     SkISize size = SkISize::Make(cinfo.fInfo.width(), cinfo.fInfo.height());
diff --git a/src/pdf/SkPDFDevice.h b/src/pdf/SkPDFDevice.h
index 8a88314..a90ea11 100644
--- a/src/pdf/SkPDFDevice.h
+++ b/src/pdf/SkPDFDevice.h
@@ -235,8 +235,7 @@
     ContentEntry* getLastContentEntry();
     void setLastContentEntry(ContentEntry* contentEntry);
 
-    // override from SkBaseDevice
-    SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) SK_OVERRIDE;
+    SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) SK_OVERRIDE;
 
     void init();
     void cleanUp(bool clearFontUsage);
diff --git a/src/utils/SkDeferredCanvas.cpp b/src/utils/SkDeferredCanvas.cpp
index 8fe9f8a..647105d 100644
--- a/src/utils/SkDeferredCanvas.cpp
+++ b/src/utils/SkDeferredCanvas.cpp
@@ -162,7 +162,7 @@
 
     GrRenderTarget* accessRenderTarget() SK_OVERRIDE;
 
-    SkBaseDevice* onCreateCompatibleDevice(const CreateInfo&) SK_OVERRIDE;
+    SkBaseDevice* onCreateDevice(const CreateInfo&, const SkPaint*) SK_OVERRIDE;
 
     SkSurface* newSurface(const SkImageInfo&, const SkSurfaceProps&) SK_OVERRIDE;
 
@@ -231,9 +231,6 @@
     void lockPixels() SK_OVERRIDE {}
     void unlockPixels() SK_OVERRIDE {}
 
-    bool allowImageFilter(const SkImageFilter*) SK_OVERRIDE {
-        return false;
-    }
     bool canHandleImageFilter(const SkImageFilter*) SK_OVERRIDE {
         return false;
     }
@@ -461,16 +458,13 @@
     return immediateDevice()->accessBitmap(false);
 }
 
-SkBaseDevice* SkDeferredDevice::onCreateCompatibleDevice(const CreateInfo& cinfo) {
-    // Save layer usage not supported, and not required by SkDeferredCanvas.
-    SkASSERT(cinfo.fUsage != kSaveLayer_Usage);
-
+SkBaseDevice* SkDeferredDevice::onCreateDevice(const CreateInfo& cinfo, const SkPaint* layerPaint) {
     // Create a compatible non-deferred device.
     // We do not create a deferred device because we know the new device
     // will not be used with a deferred canvas (there is no API for that).
     // And connecting a SkDeferredDevice to non-deferred canvas can result
     // in unpredictable behavior.
-    return immediateDevice()->onCreateCompatibleDevice(cinfo);
+    return immediateDevice()->onCreateDevice(cinfo, layerPaint);
 }
 
 SkSurface* SkDeferredDevice::newSurface(const SkImageInfo& info, const SkSurfaceProps& props) {