Revert of Revert ""Revert of eliminate config param -- it was always self's config (https://codereview.chromi… (https://codereview.chromium.org/291163005/)

Reason for revert:
broke 6 webgl/canvas tests in blink (don't know why yet)

https://storage.googleapis.com/chromium-layout-test-archives/WebKit_Mac10_7/27348/layout-test-results/results.html


Original issue's description:
> Revert ""Revert of eliminate config param -- it was always self's config (https://codereview.chromium.org/246513002/)"""
>
> This reverts commit 3dbceb4f8283b2fb1728d0daf010d036099a2eae.
>
> BUG=skia:
>
> Committed: http://code.google.com/p/skia/source/detail?r=14806

R=bsalomon@google.com, robertphillips@google.com
TBR=bsalomon@google.com, robertphillips@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: reed@google.com

Review URL: https://codereview.chromium.org/295093003

git-svn-id: http://skia.googlecode.com/svn/trunk@14826 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index 9fb041f..84f363e 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -315,14 +315,7 @@
             const SkImageInfo& prInfo = pr->info();
             SkASSERT(info.fWidth <= prInfo.fWidth);
             SkASSERT(info.fHeight <= prInfo.fHeight);
-            // We can't always assert that the two colortypes are the same, since ganesh is free
-            // to change the 32bit swizzles as needed (e.g. RGBA <--> BGRA), so we have a softer
-            // check.
-            //
-            // TODO: perhaps setPixelRef should just overwrite the values in the the bitmap anyway.
-            if (info.fColorType != prInfo.fColorType) {
-                SkASSERT(4 == info.bytesPerPixel() && 4 == prInfo.bytesPerPixel());
-            }
+            SkASSERT(info.fColorType == prInfo.fColorType);
             switch (prInfo.fAlphaType) {
                 case kIgnore_SkAlphaType:
                     SkASSERT(fInfo.fAlphaType == kIgnore_SkAlphaType);
@@ -892,7 +885,7 @@
 
     if (fPixelRef->getTexture() != NULL) {
         // Do a deep copy
-        SkPixelRef* pixelRef = fPixelRef->deepCopy(&subset);
+        SkPixelRef* pixelRef = fPixelRef->deepCopy(this->config(), &subset);
         if (pixelRef != NULL) {
             SkBitmap dst;
             dst.setConfig(this->config(), subset.width(), subset.height(), 0,
@@ -1092,7 +1085,8 @@
 }
 
 bool SkBitmap::deepCopyTo(SkBitmap* dst) const {
-    const SkColorType dstCT = this->colorType();
+    const SkBitmap::Config dstConfig = this->config();
+    const SkColorType dstCT = SkBitmapConfigToColorType(dstConfig);
 
     if (!this->canCopyTo(dstCT)) {
         return false;
@@ -1101,13 +1095,27 @@
     // If we have a PixelRef, and it supports deep copy, use it.
     // Currently supported only by texture-backed bitmaps.
     if (fPixelRef) {
-        SkAutoTUnref<SkPixelRef> pixelRef(fPixelRef->deepCopy());
-        if (pixelRef.get()) {
-            pixelRef->cloneGenID(*fPixelRef);
-            if (!dst->setConfig(pixelRef->info(), fRowBytes)) {
+        SkPixelRef* pixelRef = fPixelRef->deepCopy(dstConfig);
+        if (pixelRef) {
+            uint32_t rowBytes;
+            if (this->colorType() == dstCT) {
+                // Since there is no subset to pass to deepCopy, and deepCopy
+                // succeeded, the new pixel ref must be identical.
+                SkASSERT(fPixelRef->info() == pixelRef->info());
+                pixelRef->cloneGenID(*fPixelRef);
+                // Use the same rowBytes as the original.
+                rowBytes = fRowBytes;
+            } else {
+                // With the new config, an appropriate fRowBytes will be computed by setConfig.
+                rowBytes = 0;
+            }
+
+            SkImageInfo info = fInfo;
+            info.fColorType = dstCT;
+            if (!dst->setConfig(info, rowBytes)) {
                 return false;
             }
-            dst->setPixelRef(pixelRef, fPixelRefOrigin);
+            dst->setPixelRef(pixelRef, fPixelRefOrigin)->unref();
             return true;
         }
     }
diff --git a/src/gpu/SkGrPixelRef.cpp b/src/gpu/SkGrPixelRef.cpp
index 85de285..fd21f10 100644
--- a/src/gpu/SkGrPixelRef.cpp
+++ b/src/gpu/SkGrPixelRef.cpp
@@ -51,7 +51,8 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-static SkGrPixelRef* copyToTexturePixelRef(GrTexture* texture, const SkIRect* subset) {
+static SkGrPixelRef* copyToTexturePixelRef(GrTexture* texture, SkBitmap::Config dstConfig,
+                                           const SkIRect* subset) {
     if (NULL == texture) {
         return NULL;
     }
@@ -76,7 +77,7 @@
         topLeft = NULL;
     }
     desc.fFlags = kRenderTarget_GrTextureFlagBit | kNoStencil_GrTextureFlagBit;
-    desc.fConfig = texture->config();
+    desc.fConfig = SkBitmapConfig2GrPixelConfig(dstConfig);
 
     SkImageInfo info;
     if (!GrPixelConfig2ColorType(desc.fConfig, &info.fColorType)) {
@@ -151,7 +152,7 @@
     return NULL;
 }
 
-SkPixelRef* SkGrPixelRef::deepCopy(const SkIRect* subset) {
+SkPixelRef* SkGrPixelRef::deepCopy(SkBitmap::Config dstConfig, const SkIRect* subset) {
     if (NULL == fSurface) {
         return NULL;
     }
@@ -162,7 +163,7 @@
     // a GrTexture owned elsewhere (e.g., SkGpuDevice), and cannot live
     // independently of that texture.  Texture-backed pixel refs, on the other
     // hand, own their GrTextures, and are thus self-contained.
-    return copyToTexturePixelRef(fSurface->asTexture(), subset);
+    return copyToTexturePixelRef(fSurface->asTexture(), dstConfig, subset);
 }
 
 bool SkGrPixelRef::onReadPixels(SkBitmap* dst, const SkIRect* subset) {