Unified BeginFrame scheduling

cc/trees/layer_tree_host.cc

Index: cc/trees/layer_tree_host.cc
diff --git a/cc/trees/layer_tree_host.cc b/cc/trees/layer_tree_host.cc
index 03969f2731c73b674b22ecf45f0f4bb01eb3145c..e5266ab758994005f66311f934883cd08458378d 100644
--- a/cc/trees/layer_tree_host.cc
+++ b/cc/trees/layer_tree_host.cc
@@ -122,7 +122,8 @@ LayerTreeHost::LayerTreeHost(LayerTreeHostClient* client,
       total_frames_used_for_lcd_text_metrics_(0),
       id_(s_layer_tree_host_sequence_number.GetNext() + 1),
       next_commit_forces_redraw_(false),
-      shared_bitmap_manager_(manager) {
+      shared_bitmap_manager_(manager),
+      begin_frame_requested_(false) {
   if (settings_.accelerated_animation_enabled)
     animation_registrar_ = AnimationRegistrar::Create();
   rendering_stats_instrumentation_->set_record_rendering_stats(
@@ -1295,4 +1296,17 @@ void LayerTreeHost::BreakSwapPromises(SwapPromise::DidNotSwapReason reason) {
   swap_promise_list_.clear();
 }
 
+void LayerTreeHost::SendBeginFrame(const BeginFrameArgs& args) {
+  begin_frame_requested_ = false;
+  client_->SendBeginFrame(args);
+}
+
+void LayerTreeHost::RequestBeginFrame() {
+  // If next BeginFrame is already requested, we can use it.
+  if (begin_frame_requested_)
+    return;
+  begin_frame_requested_ = true;
+  proxy_->BeginFrameRequested();
+}
+
 }  // namespace cc