Get rid of the remaining uses of GraphicsLayer.

sky/engine/platform/graphics/gpu/DrawingBuffer.cpp

 /*
  * Copyright (c) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 492 matching lines @@
 }
 
 WebLayer* DrawingBuffer::platformLayer()
 {
     if (!m_layer) {
         m_layer = adoptPtr(Platform::current()->compositorSupport()->createExternalTextureLayer(this));
 
         m_layer->setOpaque(!m_actualAttributes.alpha);
         m_layer->setBlendBackgroundColor(m_actualAttributes.alpha);
         m_layer->setPremultipliedAlpha(m_actualAttributes.premultipliedAlpha);
-        GraphicsLayer::registerContentsLayer(m_layer->layer());
     }
 
     return m_layer->layer();
 }
 
 void DrawingBuffer::paintCompositedResultsToCanvas(ImageBuffer* imageBuffer)
 {
     if (m_context->getGraphicsResetStatusARB() != GL_NO_ERROR)
         return;
 
@@ skipping 81 matching lines @@
 
     m_colorBuffer = TextureInfo();
     m_frontColorBuffer = TextureInfo();
     m_multisampleColorBuffer = 0;
     m_depthStencilBuffer = 0;
     m_depthBuffer = 0;
     m_stencilBuffer = 0;
     m_multisampleFBO = 0;
     m_fbo = 0;
     m_contextEvictionManager.clear();
-
-    if (m_layer)
-        GraphicsLayer::unregisterContentsLayer(m_layer->layer());
 }
 
 unsigned DrawingBuffer::createColorTexture()
 {
     unsigned offscreenColorTexture = m_context->createTexture();
     if (!offscreenColorTexture)
         return 0;
 
     m_context->bindTexture(GL_TEXTURE_2D, offscreenColorTexture);
     m_context->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
@@ skipping 417 matching lines @@
 void DrawingBuffer::deleteChromiumImageForTexture(TextureInfo* info)
 {
     if (info->imageId) {
         m_context->releaseTexImage2DCHROMIUM(GL_TEXTURE_2D, info->imageId);
         m_context->destroyImageCHROMIUM(info->imageId);
         info->imageId = 0;
     }
 }
 
 } // namespace blink