Reimplement vsync latency UMA to be based on BeginImplFrame rather than BeginMainFrame

cc/scheduler/scheduler.cc

Index: cc/scheduler/scheduler.cc
diff --git a/cc/scheduler/scheduler.cc b/cc/scheduler/scheduler.cc
index d7d2e8ca6fb2ba6c2adc28c9bd06d25bcb8cc981..d14d9d037caf3849202b852194776b5e4122cf80 100644
--- a/cc/scheduler/scheduler.cc
+++ b/cc/scheduler/scheduler.cc
@@ -473,7 +473,7 @@ void Scheduler::BeginImplFrame(const BeginFrameArgs& args) {
   state_machine_.OnBeginImplFrame(args.source_id, args.sequence_number);
   devtools_instrumentation::DidBeginFrame(layer_tree_host_id_);
   compositor_timing_history_->WillBeginImplFrame(
-      state_machine_.NewActiveTreeLikely());
+      state_machine_.NewActiveTreeLikely(), args.frame_time, args.type);
   client_->WillBeginImplFrame(begin_impl_frame_tracker_.Current());
 
   ProcessScheduledActions();
@@ -624,8 +624,7 @@ void Scheduler::ProcessScheduledActions() {
       case SchedulerStateMachine::ACTION_SEND_BEGIN_MAIN_FRAME:
         compositor_timing_history_->WillBeginMainFrame(
             begin_main_frame_args_.on_critical_path,
-            begin_main_frame_args_.frame_time,
-            begin_main_frame_args_.type);
+            begin_main_frame_args_.frame_time);
         state_machine_.WillSendBeginMainFrame();
         // TODO(brianderson): Pass begin_main_frame_args_ directly to client.
         client_->ScheduledActionSendBeginMainFrame(begin_main_frame_args_);