Plumb activation time to main

cc/scheduler/scheduler.cc

Index: cc/scheduler/scheduler.cc
diff --git a/cc/scheduler/scheduler.cc b/cc/scheduler/scheduler.cc
index 4cffcd58a1674da8534ca93c61c720c7e526f47b..04ba270ba9d8c0eada284b415702f5706810a40b 100644
--- a/cc/scheduler/scheduler.cc
+++ b/cc/scheduler/scheduler.cc
@@ -92,6 +92,14 @@ void Scheduler::SetCanDraw(bool can_draw) {
 void Scheduler::NotifyReadyToActivate() {
   compositor_timing_history_->ReadyToActivate();
   state_machine_.NotifyReadyToActivate();
+  // Note the activate source-frame and timestamp
+  if (client_->SyncTreeSourceFrameNumber() != 0) {
+    ready_to_activate_source_frame_number_ =
+        client_->SyncTreeSourceFrameNumber();

[brianderson, 2017/03/30 18:32:03]

If you store this information in the ProxyImpl, you wouldn't need to expose the
SyncTreeSourceFrameNumber here. If you do need it here though, you could pass it
in as an argument to NotifyReadyToActivate.

Also, it's possible for there to be 2 NotifyReadyToActivates between 2
ScheduledActionSendBeginMainFrames with the "main frame before activate" feature
sunnyps recently implemented. So we'd need to store a vector of these pairs to
forward to the main thread.

[panicker, 2017/03/30 21:31:25]

The reason I did this here as opposed to ProxyImpl is because ProxyImpl does not
mutate BeginFrameArgs and passes around const ref where needed.
I can make it an argument to NotifyReadyToActivate as that's a bit simpler.

Making a vector makes sense to me, thanks.

+    // ready_to_activate_time_ = base::TimeTicks::Now();
+    fprintf(stderr, "\n\t\tScheduler::NotifyReadyToActivate: ptree: %d",
+            ready_to_activate_source_frame_number_);
+  }
   ProcessScheduledActions();
 }
 
@@ -627,6 +635,10 @@ void Scheduler::ProcessScheduledActions() {
             begin_main_frame_args_.frame_time);
         state_machine_.WillSendBeginMainFrame();
         // TODO(brianderson): Pass begin_main_frame_args_ directly to client.
+        // Add the args for activate.
+        begin_main_frame_args_.ready_to_activate_time = ready_to_activate_time_;
+        begin_main_frame_args_.ready_to_activate_source_frame_number =
+            ready_to_activate_source_frame_number_;
         client_->ScheduledActionSendBeginMainFrame(begin_main_frame_args_);
         break;
       case SchedulerStateMachine::ACTION_COMMIT: {