Merge 125577 - [chromium] race between CCLayerTreeHostImpl::releaseContentsTextures and CCThreadPro…

Source/WebCore/platform/graphics/chromium/cc/CCLayerTreeHostImpl.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 104 matching lines @@
 
 CCLayerTreeHostImpl::CCLayerTreeHostImpl(const CCLayerTreeSettings& settings, CCLayerTreeHostImplClient* client)
     : m_client(client)
     , m_sourceFrameNumber(-1)
     , m_rootScrollLayerImpl(0)
     , m_currentlyScrollingLayerImpl(0)
     , m_scrollingLayerIdFromPreviousTree(-1)
     , m_settings(settings)
     , m_deviceScaleFactor(1)
     , m_visible(true)
-    , m_contentsTexturesWerePurgedSinceLastCommit(false)
+    , m_contentsTexturesPurged(false)
     , m_memoryAllocationLimitBytes(CCPrioritizedTextureManager::defaultMemoryAllocationLimit())
     , m_pageScale(1)
     , m_pageScaleDelta(1)
     , m_sentPageScaleDelta(1)
     , m_minPageScale(0)
     , m_maxPageScale(0)
     , m_backgroundColor(0)
     , m_hasTransparentBackground(false)
     , m_needsAnimateLayers(false)
     , m_pinchGestureActive(false)
@@ skipping 16 matching lines @@
 void CCLayerTreeHostImpl::beginCommit()
 {
 }
 
 void CCLayerTreeHostImpl::commitComplete()
 {
     TRACE_EVENT0("cc", "CCLayerTreeHostImpl::commitComplete");
     // Recompute max scroll position; must be after layer content bounds are
     // updated.
     updateMaxScrollPosition();
-    m_contentsTexturesWerePurgedSinceLastCommit = false;
 }
 
 bool CCLayerTreeHostImpl::canDraw()
 {
     if (!m_rootLayerImpl) {
         TRACE_EVENT_INSTANT0("cc", "CCLayerTreeHostImpl::canDraw no root layer");
         return false;
     }
     if (deviceViewportSize().isEmpty()) {
         TRACE_EVENT_INSTANT0("cc", "CCLayerTreeHostImpl::canDraw empty viewport");
         return false;
     }
     if (!m_layerRenderer) {
         TRACE_EVENT_INSTANT0("cc", "CCLayerTreeHostImpl::canDraw no layerRenderer");
         return false;
     }
-    if (m_contentsTexturesWerePurgedSinceLastCommit) {
+    if (m_contentsTexturesPurged) {
         TRACE_EVENT_INSTANT0("cc", "CCLayerTreeHostImpl::canDraw contents textures purged");
         return false;
     }
     return true;
 }
 
 CCGraphicsContext* CCLayerTreeHostImpl::context() const
 {
     return m_context.get();
 }
@@ skipping 322 matching lines @@
 
     if (!calculateRenderPasses(frame))
         return false;
 
     // If we return true, then we expect drawLayers() to be called before this function is called again.
     return true;
 }
 
 void CCLayerTreeHostImpl::releaseContentsTextures()
 {
+    if (m_contentsTexturesPurged)
+        return;
     m_resourceProvider->deleteOwnedResources(CCRenderer::ContentPool);
-    m_contentsTexturesWerePurgedSinceLastCommit = true;
+    m_contentsTexturesPurged = true;
     m_client->setNeedsCommitOnImplThread();
 }
 
 void CCLayerTreeHostImpl::setMemoryAllocationLimitBytes(size_t bytes)
 {
     if (m_memoryAllocationLimitBytes == bytes)
         return;
     m_memoryAllocationLimitBytes = bytes;
 
     ASSERT(bytes);
@@ skipping 664 matching lines @@
 
     CCScrollbarAnimationController* scrollbarController = layer->scrollbarAnimationController();
     if (scrollbarController && scrollbarController->animate(monotonicTime))
         m_client->setNeedsRedrawOnImplThread();
 
     for (size_t i = 0; i < layer->children().size(); ++i)
         animateScrollbarsRecursive(layer->children()[i].get(), monotonicTime);
 }
 
 } // namespace WebCore