Merge 126540 - [chromium] Fix lost context when textures are evicted

Source/WebCore/platform/graphics/chromium/cc/CCThreadProxy.cpp

 /*
  * Copyright (C) 2011 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:
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
@@ skipping 867 matching lines @@
 
 size_t CCThreadProxy::maxPartialTextureUpdates() const
 {
     return CCTextureUpdateController::maxPartialTextureUpdates();
 }
 
 void CCThreadProxy::recreateContextOnImplThread(CCCompletionEvent* completion, CCGraphicsContext* contextPtr, bool* recreateSucceeded, LayerRendererCapabilities* capabilities)
 {
     TRACE_EVENT0("cc", "CCThreadProxy::recreateContextOnImplThread");
     ASSERT(isImplThread());
-    m_layerTreeHost->deleteContentsTexturesOnImplThread(m_layerTreeHostImpl->resourceProvider());
+    if (!m_layerTreeHostImpl->contentsTexturesPurged())
+        m_layerTreeHost->deleteContentsTexturesOnImplThread(m_layerTreeHostImpl->resourceProvider());
     *recreateSucceeded = m_layerTreeHostImpl->initializeLayerRenderer(adoptPtr(contextPtr), textureUploader);
     if (*recreateSucceeded) {
         *capabilities = m_layerTreeHostImpl->layerRendererCapabilities();
         m_schedulerOnImplThread->didRecreateContext();
     }
     completion->signal();
 }
 
 void CCThreadProxy::implSideRenderingStatsOnImplThread(CCCompletionEvent* completion, CCRenderingStats* stats)
 {
     ASSERT(isImplThread());
     m_layerTreeHostImpl->renderingStats(*stats);
     completion->signal();
 }
 
 } // namespace WebCore