Use a lock to deal with concurrent access to the m_evictedBackings

cc/prioritized_resource.cc

 // Copyright 2012 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 "cc/prioritized_resource.h"
 
 #include "cc/platform_color.h"
 #include "cc/prioritized_resource_manager.h"
 #include "cc/priority_calculator.h"
 #include "cc/proxy.h"
@@ skipping 89 matching lines @@
 
     // The component order may be bgra if we uploaded bgra pixels to rgba
     // texture. Mark contents as swizzled if image component order is
     // different than texture format.
     m_contentsSwizzled = !PlatformColor::sameComponentOrder(m_format);
 }
 
 void PrioritizedResource::link(Backing* backing)
 {
     DCHECK(backing);
-    CHECK(!backing->m_owner);
-    CHECK(!m_backing);
+    DCHECK(!backing->m_owner);
+    DCHECK(!m_backing);
 
     m_backing = backing;
     m_backing->m_owner = this;
 }
 
 void PrioritizedResource::unlink()
 {
     DCHECK(m_backing);
-    CHECK(m_backing->m_owner == this);
+    DCHECK(m_backing->m_owner == this);
 
     m_backing->m_owner = 0;
     m_backing = 0;
 }
 
 void PrioritizedResource::setToSelfManagedMemoryPlaceholder(size_t bytes)
 {
     setDimensions(gfx::Size(), GL_RGBA);
     setIsSelfManaged(true);
     m_bytes = bytes;
 }
 
 PrioritizedResource::Backing::Backing(unsigned id, ResourceProvider* resourceProvider, gfx::Size size, GLenum format)
     : Resource(id, size, format)
     , m_owner(0)
     , m_priorityAtLastPriorityUpdate(PriorityCalculator::lowestPriority())
     , m_wasAbovePriorityCutoffAtLastPriorityUpdate(false)
     , m_inDrawingImplTree(false)
     , m_resourceHasBeenDeleted(false)
-    , m_inMainThreadEvictedList(false)
 #ifndef NDEBUG
     , m_resourceProvider(resourceProvider)
 #endif
 {
 }
 
 PrioritizedResource::Backing::~Backing()
 {
     DCHECK(!m_owner);
     DCHECK(m_resourceHasBeenDeleted);
-    CHECK(!m_inMainThreadEvictedList);
 }
 
 void PrioritizedResource::Backing::deleteResource(ResourceProvider* resourceProvider)
 {
     DCHECK(!proxy() || proxy()->isImplThread());
     DCHECK(!m_resourceHasBeenDeleted);
 #ifndef NDEBUG
     DCHECK(resourceProvider == m_resourceProvider);
 #endif
 
@@ skipping 42 matching lines @@
 }
 
 const Proxy* PrioritizedResource::Backing::proxy() const
 {
     if (!m_owner || !m_owner->resourceManager())
         return 0;
     return m_owner->resourceManager()->proxyForDebug();
 }
 
 }  // namespace cc