Move overdraw tracking code from GraphicsContext to CanvasRenderingContext2D

Source/platform/graphics/RecordingImageBufferSurface.cpp

 // Copyright 2014 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 "platform/graphics/RecordingImageBufferSurface.h"
 
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/ImageBuffer.h"
@@ skipping 27 matching lines @@
         m_imageBuffer->resetCanvas(m_currentFrame->getRecordingCanvas());
     }
     m_didRecordDrawCommandsInCurrentFrame = false;
     return true;
 }
 
 void RecordingImageBufferSurface::setImageBuffer(ImageBuffer* imageBuffer)
 {
     m_imageBuffer = imageBuffer;
     if (m_currentFrame && m_imageBuffer) {
-        m_imageBuffer->context()->setClient(this);
         m_imageBuffer->resetCanvas(m_currentFrame->getRecordingCanvas());
     }
     if (m_fallbackSurface) {
         m_fallbackSurface->setImageBuffer(imageBuffer);
-        m_imageBuffer->context()->setClient(0);
     }
 }
 
 void RecordingImageBufferSurface::willAccessPixels()
 {
     if (m_fallbackSurface)
         m_fallbackSurface->willAccessPixels();
     else
         fallBackToRasterCanvas();
 }
@@ skipping 13 matching lines @@
         m_previousFrame.clear();
     }
 
     if (m_currentFrame) {
         RefPtr<SkPicture> currentPicture = adoptRef(m_currentFrame->endRecording());
         currentPicture->playback(m_fallbackSurface->canvas());
         m_currentFrame.clear();
     }
 
     if (m_imageBuffer) {
-        m_imageBuffer->context()->setClient(0);
         m_imageBuffer->resetCanvas(m_fallbackSurface->canvas());
         m_imageBuffer->context()->setAccelerated(m_fallbackSurface->isAccelerated());
     }
 
 }
 
 PassRefPtr<SkImage> RecordingImageBufferSurface::newImageSnapshot() const
 {
     if (!m_fallbackSurface)
         const_cast<RecordingImageBufferSurface*>(this)->fallBackToRasterCanvas();
@@ skipping 170 matching lines @@
 
 void RecordingImageBufferSurface::setIsHidden(bool hidden)
 {
     if (m_fallbackSurface)
         m_fallbackSurface->setIsHidden(hidden);
     else
         ImageBufferSurface::setIsHidden(hidden);
 }
 
 } // namespace blink