[cc] Evict UIResources when the renderer is not visible

cc/trees/layer_tree_host.h

Index: cc/trees/layer_tree_host.h
diff --git a/cc/trees/layer_tree_host.h b/cc/trees/layer_tree_host.h
index e362f84b4ca09789afc7c0ea734edab6f5039e9a..aec2d5fa28503ed45f56c759646c37d109f8a1a3 100644
--- a/cc/trees/layer_tree_host.h
+++ b/cc/trees/layer_tree_host.h
@@ -90,6 +90,7 @@ struct CC_EXPORT UIResourceRequest {
   enum UIResourceRequestType {
     UIResourceCreate,
     UIResourceDelete,
+    UIResourceEvictionRecreated,
     UIResourceInvalidRequest
   };
 
@@ -98,6 +99,7 @@ struct CC_EXPORT UIResourceRequest {
   UIResourceRequestType type;
   UIResourceId id;
   scoped_refptr<UIResourceBitmap> bitmap;
+  uint64 eviction_count_recreated;
 };
 
 class CC_EXPORT LayerTreeHost : NON_EXPORTED_BASE(public RateLimiterClient) {
@@ -287,6 +289,13 @@ class CC_EXPORT LayerTreeHost : NON_EXPORTED_BASE(public RateLimiterClient) {
   // Deletes a UI resource.  May safely be called more than once.
   virtual void DeleteUIResource(UIResourceId id);
 
+  // Record the eviction count sent by the LayerTreeHostImpl at BeginFrame.
+  // If the value of |ui_resource_eviction_count| is greater than the value of
+  // |ui_resource_eviction_count_recreated_| then add the recreation
+  // of all UI resources to the UIResourceRequestQueue and return true.
+  // Otherwise return false.
+  bool SetUIResourceEvictionCount(uint64 ui_resource_eviction_count);
+
   bool UsingSharedMemoryResources();
   int id() const { return tree_id_; }
 
@@ -323,14 +332,13 @@ class CC_EXPORT LayerTreeHost : NON_EXPORTED_BASE(public RateLimiterClient) {
 
   bool AnimateLayersRecursive(Layer* current, base::TimeTicks time);
 
-  void RecreateUIResources(bool resource_lost);
-
   typedef base::hash_map<UIResourceId, UIResourceClient*> UIResourceClientMap;
   UIResourceClientMap ui_resource_client_map_;
   int next_ui_resource_id_;
 
   typedef std::list<UIResourceRequest> UIResourceRequestQueue;
   UIResourceRequestQueue ui_resource_request_queue_;
+  uint64 ui_resource_eviction_count_recreated_;
 
   void CalculateLCDTextMetricsCallback(Layer* layer);