[cc] Evict UIResources when the renderer is not visible

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 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_TREES_LAYER_TREE_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <list>
+#include <set>
 #include <string>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/containers/hash_tables.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
 #include "cc/animation/animation_events.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/base/cc_export.h"
@@ skipping 383 matching lines @@
   scoped_ptr<base::Value> AsValue() const { return AsValueWithFrame(NULL); }
   scoped_ptr<base::Value> AsValueWithFrame(FrameData* frame) const;
   scoped_ptr<base::Value> ActivationStateAsValue() const;
 
   bool page_scale_animation_active() const { return !!page_scale_animation_; }
 
   void CreateUIResource(UIResourceId uid,
                         scoped_refptr<UIResourceBitmap> bitmap);
   // Deletes a UI resource.  May safely be called more than once.
   void DeleteUIResource(UIResourceId uid);
-  void DeleteAllUIResources();
+  void EvictAllUIResources();
+  bool EvictedUIResourcesExist() const;
 
   ResourceProvider::ResourceId ResourceIdForUIResource(UIResourceId uid) const;
 
  protected:
   LayerTreeHostImpl(
       const LayerTreeSettings& settings,
       LayerTreeHostImplClient* client,
       Proxy* proxy,
       RenderingStatsInstrumentation* rendering_stats_instrumentation);
 
@@ skipping 55 matching lines @@
 
   void UpdateCurrentFrameTime(base::TimeTicks* ticks, base::Time* now) const;
 
   void StartScrollbarAnimationRecursive(LayerImpl* layer, base::TimeTicks time);
   void SetManagedMemoryPolicy(const ManagedMemoryPolicy& policy,
                               bool zero_budget);
   void EnforceManagedMemoryPolicy(const ManagedMemoryPolicy& policy);
 
   void DidInitializeVisibleTile();
 
+  void MarkUIResourceNotEvicted(UIResourceId uid);
+
   typedef base::hash_map<UIResourceId, ResourceProvider::ResourceId>
       UIResourceMap;
   UIResourceMap ui_resource_map_;
 
+  // Resources that were evicted by EvictAllUIResources. Resources are removed
+  // from this when they are touched by a create or destroy from the UI resource
+  // request queue.
+  std::set<UIResourceId> evicted_ui_resources_;
+
   scoped_ptr<OutputSurface> output_surface_;
   scoped_refptr<ContextProvider> offscreen_context_provider_;
 
   // |resource_provider_| and |tile_manager_| can be NULL, e.g. when using tile-
   // free rendering - see OutputSurface::ForcedDrawToSoftwareDevice().
   scoped_ptr<ResourceProvider> resource_provider_;
   scoped_ptr<TileManager> tile_manager_;
   scoped_ptr<Renderer> renderer_;
 
   // Tree currently being drawn.
@@ skipping 99 matching lines @@
 
   // Optional callback to notify of new tree activations.
   base::Closure tree_activation_callback_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_