cc: Add command line switch to control resource usage for impl-side painting.

cc/resources/resource_pool.h

 // 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.
 
 #ifndef CC_RESOURCES_RESOURCE_POOL_H_
 #define CC_RESOURCES_RESOURCE_POOL_H_
 
 #include <list>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 24 matching lines @@
   }
 
   virtual ~ResourcePool();
 
   ResourceProvider* resource_provider() { return resource_provider_; }
 
   scoped_ptr<ResourcePool::Resource> AcquireResource(
       const gfx::Size&, GLenum format);
   void ReleaseResource(scoped_ptr<ResourcePool::Resource>);
 
-  void SetMaxMemoryUsageBytes(size_t max_memory_usage_bytes);
+  void SetMaxMemoryUsageBytes(
+      size_t max_memory_usage_bytes,
+      size_t max_unused_memory_usage_bytes);
 
  protected:
   explicit ResourcePool(ResourceProvider* resource_provider);
 
+  bool MemoryUsageTooHigh();
+
  private:
   ResourceProvider* resource_provider_;
   size_t max_memory_usage_bytes_;
+  size_t max_unused_memory_usage_bytes_;
   size_t memory_usage_bytes_;
+  size_t unused_memory_usage_bytes_;
 
   typedef std::list<Resource*> ResourceList;
   ResourceList resources_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourcePool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_POOL_H_