Implement image-rendering:pixelated for accelerated 2D canvases.

Source/core/html/HTMLCanvasElement.cpp

Index: Source/core/html/HTMLCanvasElement.cpp
diff --git a/Source/core/html/HTMLCanvasElement.cpp b/Source/core/html/HTMLCanvasElement.cpp
index 9cecdc45291136d9fab1fc1e9739d9b22dd1018c..1974da85e131469f196f7f118e7ac0baa78a5320 100644
--- a/Source/core/html/HTMLCanvasElement.cpp
+++ b/Source/core/html/HTMLCanvasElement.cpp
@@ -87,6 +87,7 @@ inline HTMLCanvasElement::HTMLCanvasElement(Document& document)
     , m_didFailToCreateImageBuffer(false)
     , m_didClearImageBuffer(false)
 {
+    setHasCustomStyleCallbacks();
 }
 
 DEFINE_NODE_FACTORY(HTMLCanvasElement)
@@ -120,6 +121,15 @@ RenderObject* HTMLCanvasElement::createRenderer(RenderStyle* style)
     return HTMLElement::createRenderer(style);
 }
 
+void HTMLCanvasElement::didRecalcStyle(StyleRecalcChange)
+{
+    //printf("HTMLCanvasElement::didRecalcStyle\n");
+    if (!hasImageBuffer())
+        return;
+    //printf("HTMLCanvasElement::didRecalcStyle hasImageBuffer\n");
+    m_imageBuffer->setFilterLevel(computedStyle()->imageRendering() == ImageRenderingPixelated ? SkPaint::kNone_FilterLevel : SkPaint::kLow_FilterLevel);
+}
+
 Node::InsertionNotificationRequest HTMLCanvasElement::insertedInto(ContainerNode* node)
 {
     setIsInCanvasSubtree(true);
@@ -534,7 +544,7 @@ PassOwnPtr<ImageBufferSurface> HTMLCanvasElement::createImageBufferSurface(const
 
     OwnPtr<RecordingImageBufferFallbackSurfaceFactory> surfaceFactory = createSurfaceFactory(deviceSize, msaaSampleCount);
 
-    if (RuntimeEnabledFeatures::displayList2dCanvasEnabled()) {
+    if (RuntimeEnabledFeatures::displayList2dCanvasEnabled() && false) {
         OwnPtr<ImageBufferSurface> surface = adoptPtr(new RecordingImageBufferSurface(deviceSize, surfaceFactory.release(), opacityMode));
         if (surface->isValid())
             return surface.release();
@@ -577,6 +587,8 @@ void HTMLCanvasElement::createImageBufferInternal()
     m_imageBuffer = ImageBuffer::create(surface.release());
     m_imageBuffer->setClient(this);
 
+    m_imageBuffer->setFilterLevel(computedStyle()->imageRendering() == ImageRenderingPixelated ? SkPaint::kNone_FilterLevel : SkPaint::kLow_FilterLevel);
+
     m_didFailToCreateImageBuffer = false;
 
     updateExternallyAllocatedMemory();