(not for review yet)

cc/trees/layer_tree_host_impl.h

Index: cc/trees/layer_tree_host_impl.h
diff --git a/cc/trees/layer_tree_host_impl.h b/cc/trees/layer_tree_host_impl.h
index b908bc135fa7bdef68afb54a5d74edd7f8eacabf..6d6ac6cf5a10050007c35409b12201d14ec5b58d 100644
--- a/cc/trees/layer_tree_host_impl.h
+++ b/cc/trees/layer_tree_host_impl.h
@@ -323,6 +323,10 @@ class CC_EXPORT LayerTreeHostImpl
     return animation_registrar_.get();
   }
 
+  uint64 ui_resource_eviction_count() const {
+    return ui_resource_eviction_count_;
+  }
+
   void SetDebugState(const LayerTreeDebugState& new_debug_state);
   const LayerTreeDebugState& debug_state() const { return debug_state_; }
 
@@ -565,6 +569,11 @@ class CC_EXPORT LayerTreeHostImpl
 
   bool need_to_update_visible_tiles_before_draw_;
 
+  // The number of times that UI resources have been evicted since creation.
+  // When doing a commit, the LayerTreeHost will acknowledge the most recent
+  // eviction for which it has recreated all UI resources.
+  uint64 ui_resource_eviction_count_;
+
   // Optional callback to notify of new tree activations.
   base::Closure tree_activation_callback_;