Add compositor support for the LatencyInfo.

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 ffdfb5fb58b6d009c7465a4b39f3c10348e37763..3a30dbb99af9c02f605c829d0d810bfb11ab364d 100644
--- a/cc/trees/layer_tree_host_impl.h
+++ b/cc/trees/layer_tree_host_impl.h
@@ -14,6 +14,7 @@
 #include "cc/animation/animation_events.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/base/cc_export.h"
+#include "cc/debug/latency_info.h"
 #include "cc/input/input_handler.h"
 #include "cc/input/top_controls_manager_client.h"
 #include "cc/layers/layer_lists.h"
@@ -234,6 +235,8 @@ class CC_EXPORT LayerTreeHostImpl : public InputHandlerClient,
   void SetNeedsCommit() { client_->SetNeedsCommitOnImplThread(); }
   void SetNeedsRedraw() { client_->SetNeedsRedrawOnImplThread(); }
 
+  void SetLatencyInfo(const LatencyInfo&);
+
   size_t memory_allocation_limit_bytes() const {
     return managed_memory_policy_.bytes_limit_when_visible;
   }
@@ -469,6 +472,8 @@ class CC_EXPORT LayerTreeHostImpl : public InputHandlerClient,
 
   RenderingStatsInstrumentation* rendering_stats_instrumentation_;
 
+  LatencyInfo latency_info_;
+
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };