Make 2D canvas smarter about chosing whether or not to use GPU acceleration

third_party/WebKit/Source/core/frame/ImageBitmap.cpp

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "core/frame/ImageBitmap.h"
 
 #include "core/html/HTMLCanvasElement.h"
 #include "core/html/HTMLVideoElement.h"
 #include "core/html/ImageData.h"
@@ skipping 72 matching lines @@
 }
 
 ImageBitmap::ImageBitmap(HTMLCanvasElement* canvas, const IntRect& cropRect)
     : m_imageElement(nullptr)
     , m_cropRect(cropRect)
     , m_bitmapOffset(IntPoint())
 {
     IntRect srcRect = intersection(cropRect, IntRect(IntPoint(), canvas->size()));
     m_bitmapRect = IntRect(IntPoint(std::max(0, -cropRect.x()), std::max(0, -cropRect.y())), srcRect.size());
     ASSERT(canvas->isPaintable());
-    m_bitmap = cropImage(canvas->copiedImage(BackBuffer), cropRect);
+    m_bitmap = cropImage(canvas->copiedImage(BackBuffer, PreferAcceleration), cropRect);
 }
 
 ImageBitmap::ImageBitmap(ImageData* data, const IntRect& cropRect)
     : m_imageElement(nullptr)
     , m_cropRect(cropRect)
     , m_bitmapOffset(IntPoint())
 {
     IntRect srcRect = intersection(cropRect, IntRect(IntPoint(), data->size()));
     OwnPtr<ImageBuffer> buffer = ImageBuffer::create(data->size());
     if (!buffer)
@@ skipping 86 matching lines @@
 }
 
 PassRefPtr<Image> ImageBitmap::bitmapImage() const
 {
     ASSERT((m_imageElement || m_bitmap || !m_bitmapRect.width() || !m_bitmapRect.height()) && (!m_imageElement || !m_bitmap));
     if (m_imageElement)
         return m_imageElement->cachedImage()->image();
     return m_bitmap;
 }
 
-PassRefPtr<Image> ImageBitmap::getSourceImageForCanvas(SourceImageStatus* status) const
+PassRefPtr<Image> ImageBitmap::getSourceImageForCanvas(SourceImageStatus* status, AccelerationHint) const
 {
     *status = NormalSourceImageStatus;
     return bitmapImage();
 }
 
 void ImageBitmap::adjustDrawRects(FloatRect* srcRect, FloatRect* dstRect) const
 {
     FloatRect intersectRect = intersection(m_bitmapRect, *srcRect);
     FloatRect newSrcRect = intersectRect;
     newSrcRect.move(m_bitmapOffset - m_bitmapRect.location());
@@ skipping 10 matching lines @@
     return FloatSize(width(), height());
 }
 
 DEFINE_TRACE(ImageBitmap)
 {
     visitor->trace(m_imageElement);
     ImageLoaderClient::trace(visitor);
 }
 
 } // namespace blink