cc: Add main frame timing info to frame timing tracker.

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
diff --git a/cc/layers/layer_impl.cc b/cc/layers/layer_impl.cc
index b4ba876d0944697bcabe19e15835c070f9f01811..3ffeb730bfcb35e7c2316b5838e8610ea016cca3 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -1044,6 +1044,11 @@ void LayerImpl::PassFrameTimingRequests(
   SetNeedsPushProperties();
 }
 
+void LayerImpl::GatherFrameTimingRequestIds(std::vector<int64_t>* request_ids) {
+  for (const auto& request : frame_timing_requests_)
+    request_ids->push_back(request.id());
+}
+
 void LayerImpl::SetTransform(const gfx::Transform& transform) {
   if (transform_ == transform)
     return;