cc: Prevent the tile manager from allocating more memory than allowed.

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();
 
   scoped_ptr<ResourcePool::Resource> AcquireResource(gfx::Size size,
                                                      GLenum format);
   void ReleaseResource(scoped_ptr<ResourcePool::Resource>);
 
   void SetMemoryUsageLimits(size_t max_memory_usage_bytes,
                             size_t max_unused_memory_usage_bytes,
-                            size_t num_resources_limit);
+                            size_t max_resource_count);
+
+  void ReduceMemoryUsage();
 
   size_t total_memory_usage_bytes() const {
     return memory_usage_bytes_;
   }
   size_t acquired_memory_usage_bytes() const {
     return memory_usage_bytes_ - unused_memory_usage_bytes_;
   }
-  size_t NumResources() const { return resources_.size(); }
+  size_t acquired_resource_count() const {
+    return resource_count_ - unused_resources_.size();
+  }
 
  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 max_resource_count_;
   size_t memory_usage_bytes_;
   size_t unused_memory_usage_bytes_;
-  size_t num_resources_limit_;
+  size_t resource_count_;
 
   typedef std::list<Resource*> ResourceList;
-  ResourceList resources_;
+  ResourceList unused_resources_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourcePool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_POOL_H_