cc: Keep most recently used resources at the front of resource queue.

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 <deque>
 
 #include "base/containers/scoped_ptr_map.h"
@@ skipping 101 matching lines @@
 
   ResourceProvider* resource_provider_;
   const GLenum target_;
   size_t max_memory_usage_bytes_;
   size_t max_resource_count_;
   size_t in_use_memory_usage_bytes_;
   size_t total_memory_usage_bytes_;
   size_t total_resource_count_;
 
   using ResourceDeque = ScopedPtrDeque<PoolResource>;
+  // Holds least recently used resources at the front of the queue.

[reveman, 2015/11/02 06:07:51]

why don't we just revert this order and keep the least recently used at the back
instead to avoid the reverse iterator stuff?

[prashant.n, 2015/11/02 17:56:45]

Should we do this or leave as it is? Do let me know your opinion, so that I can
modify.

[reveman, 2015/11/02 18:16:29]

Unless I missing something, reverting the order is just a matter of changing a
push_back to push_front and a few calls to take_front()/front() to
take_back()/back(). That seems a lot simpler and than the reverse iterator
changes and unless there's something more to it I'd prefer that approach.

   ResourceDeque unused_resources_;
   ResourceDeque busy_resources_;
 
   using ResourceMap = base::ScopedPtrMap<ResourceId, scoped_ptr<PoolResource>>;
   ResourceMap in_use_resources_;
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
   bool evict_expired_resources_pending_;
   base::TimeDelta resource_expiration_delay_;
 
   base::WeakPtrFactory<ResourcePool> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourcePool);
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_RESOURCE_POOL_H_