Unified BeginFrame scheduling

cc/scheduler/scheduler_settings.cc

Index: cc/scheduler/scheduler_settings.cc
diff --git a/cc/scheduler/scheduler_settings.cc b/cc/scheduler/scheduler_settings.cc
index ea714e34b0dbae4fd3fc49fc0c874f758e739add..34b44526f82c5ba3147afa210ec1e2288f39c2a8 100644
--- a/cc/scheduler/scheduler_settings.cc
+++ b/cc/scheduler/scheduler_settings.cc
@@ -10,7 +10,8 @@
 namespace cc {
 
 SchedulerSettings::SchedulerSettings()
-    : begin_frame_scheduling_enabled(true),
+    : begin_frame_receiver(true),
+      begin_frame_publisher(false),
       main_frame_before_draw_enabled(true),
       main_frame_before_activation_enabled(false),
       impl_side_painting(false),
@@ -21,7 +22,8 @@ SchedulerSettings::SchedulerSettings()
 }
 
 SchedulerSettings::SchedulerSettings(const LayerTreeSettings& settings)
-    : begin_frame_scheduling_enabled(settings.begin_frame_scheduling_enabled),
+    : begin_frame_receiver(settings.begin_frame_scheduling_enabled),
+      begin_frame_publisher(settings.begin_frame_publisher),
       main_frame_before_draw_enabled(settings.main_frame_before_draw_enabled),
       main_frame_before_activation_enabled(
           settings.main_frame_before_activation_enabled),
@@ -33,6 +35,8 @@ SchedulerSettings::SchedulerSettings(const LayerTreeSettings& settings)
       using_synchronous_renderer_compositor(
           settings.using_synchronous_renderer_compositor),
       throttle_frame_production(settings.throttle_frame_production) {
+  if (begin_frame_receiver)
+    DCHECK(!begin_frame_publisher);
 }
 
 SchedulerSettings::~SchedulerSettings() {}
@@ -41,8 +45,10 @@ scoped_refptr<base::debug::ConvertableToTraceFormat>
 SchedulerSettings::AsValue() const {
   scoped_refptr<base::debug::TracedValue> state =
       new base::debug::TracedValue();
-  state->SetBoolean("begin_frame_scheduling_enabled",
-                    begin_frame_scheduling_enabled);
+  state->SetBoolean("begin_frame_receiver",
+                    begin_frame_receiver);
+  state->SetBoolean("begin_frame_publisher",
+                    begin_frame_publisher);
   state->SetBoolean("main_frame_before_draw_enabled",
                     main_frame_before_draw_enabled);
   state->SetBoolean("main_frame_before_activation_enabled",