Refactoring ImageBuffer to decouple it from Canvas2DLayerBridge

Source/core/svg/graphics/SVGImage.cpp

Index: Source/core/svg/graphics/SVGImage.cpp
diff --git a/Source/core/svg/graphics/SVGImage.cpp b/Source/core/svg/graphics/SVGImage.cpp
index 479856650550cc63ce863e0e9d7955ba30f7fce8..98c8fd62e2b869b091bf6b2c40bcc8096606479b 100644
--- a/Source/core/svg/graphics/SVGImage.cpp
+++ b/Source/core/svg/graphics/SVGImage.cpp
@@ -48,6 +48,7 @@
 #include "platform/LengthFunctions.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/graphics/ImageObserver.h"
+#include "platform/graphics/UnacceleratedImageBufferSurface.h"
 #include "wtf/PassRefPtr.h"
 
 namespace WebCore {
@@ -192,14 +193,15 @@ PassRefPtr<NativeImageSkia> SVGImage::nativeImageForCurrentFrame()
     if (!m_page)
         return 0;
 
-    OwnPtr<ImageBuffer> buffer = ImageBuffer::create(size(), 1);
-    if (!buffer) // failed to allocate image
+    OwnPtr<ImageBufferSurface> surface = adoptPtr(new UnacceleratedImageBufferSurface(size()));
+    if (!surface->isValid())
         return 0;
+    ImageBuffer buffer(surface.release());
 
-    drawForContainer(buffer->context(), size(), 1, rect(), rect(), CompositeSourceOver, blink::WebBlendModeNormal);
+    drawForContainer(buffer.context(), size(), 1, rect(), rect(), CompositeSourceOver, blink::WebBlendModeNormal);
 
     // FIXME: WK(Bug 113657): We should use DontCopyBackingStore here.
-    return buffer->copyImage(CopyBackingStore)->nativeImageForCurrentFrame();
+    return buffer.copyImage(CopyBackingStore)->nativeImageForCurrentFrame();
 }
 
 void SVGImage::drawPatternForContainer(GraphicsContext* context, const FloatSize containerSize, float zoom, const FloatRect& srcRect,
@@ -220,11 +222,12 @@ void SVGImage::drawPatternForContainer(GraphicsContext* context, const FloatSize
     FloatRect imageBufferSize = zoomedContainerRect;
     imageBufferSize.scale(imageBufferScale.width(), imageBufferScale.height());
 
-    OwnPtr<ImageBuffer> buffer = ImageBuffer::create(expandedIntSize(imageBufferSize.size()), 1);
-    if (!buffer) // Failed to allocate buffer.
+    OwnPtr<ImageBufferSurface> surface = adoptPtr(new UnacceleratedImageBufferSurface(expandedIntSize(imageBufferSize.size())));
+    if (!surface->isValid())
         return;
-    drawForContainer(buffer->context(), containerSize, zoom, imageBufferSize, zoomedContainerRect, CompositeSourceOver, blink::WebBlendModeNormal);
-    RefPtr<Image> image = buffer->copyImage(DontCopyBackingStore, Unscaled);
+    ImageBuffer buffer(surface.release());
+    drawForContainer(buffer.context(), containerSize, zoom, imageBufferSize, zoomedContainerRect, CompositeSourceOver, blink::WebBlendModeNormal);
+    RefPtr<Image> image = buffer.copyImage(DontCopyBackingStore, Unscaled);
 
     // Adjust the source rect and transform due to the image buffer's scaling.
     FloatRect scaledSrcRect = srcRect;