Revert "cc: Don't record first two frames in CompositorTimingHistory"

cc/scheduler/compositor_timing_history.cc

Index: cc/scheduler/compositor_timing_history.cc
diff --git a/cc/scheduler/compositor_timing_history.cc b/cc/scheduler/compositor_timing_history.cc
index e9be0b03e3314194c83e32998244cd4fa681b195..34726d5ddf8795792d6f0fa7a85aeef5ba9193de 100644
--- a/cc/scheduler/compositor_timing_history.cc
+++ b/cc/scheduler/compositor_timing_history.cc
@@ -38,7 +38,6 @@ namespace {
 // second.
 // TODO(brianderson): Fine tune the percentiles below.
 const size_t kDurationHistorySize = 60;
-const size_t kDrawsBeforeEstimatesAffected = 2;
 const double kBeginMainFrameToCommitEstimationPercentile = 90.0;
 const double kCommitToReadyToActivateEstimationPercentile = 90.0;
 const double kPrepareTilesEstimationPercentile = 90.0;
@@ -199,7 +198,6 @@ CompositorTimingHistory::CompositorTimingHistory(
     UMACategory uma_category,
     RenderingStatsInstrumentation* rendering_stats_instrumentation)
     : enabled_(false),
-      draws_left_before_estimates_affected_(0),
       begin_main_frame_to_commit_duration_history_(kDurationHistorySize),
       commit_to_ready_to_activate_duration_history_(kDurationHistorySize),
       prepare_tiles_duration_history_(kDurationHistorySize),
@@ -246,18 +244,8 @@ base::TimeTicks CompositorTimingHistory::Now() const {
   return base::TimeTicks::Now();
 }
 
-bool CompositorTimingHistory::AffectsEstimate() const {
-  return enabled_ && (draws_left_before_estimates_affected_ == 0);
-}
-
 void CompositorTimingHistory::SetRecordingEnabled(bool enabled) {
-  if (enabled == enabled_)
-    return;
-
   enabled_ = enabled;
-
-  if (enabled_)
-    draws_left_before_estimates_affected_ = kDrawsBeforeEstimatesAffected;
 }
 
 base::TimeDelta
@@ -307,15 +295,13 @@ void CompositorTimingHistory::DidCommit() {
   // of our predictions.
   base::TimeDelta begin_main_frame_to_commit_estimate =
       BeginMainFrameToCommitDurationEstimate();
-
+  uma_reporter_->AddBeginMainFrameToCommitDuration(
+      begin_main_frame_to_commit_duration, begin_main_frame_to_commit_estimate,
+      enabled_);
   rendering_stats_instrumentation_->AddBeginMainFrameToCommitDuration(
       begin_main_frame_to_commit_duration, begin_main_frame_to_commit_estimate);
 
-  bool affects_estimate = AffectsEstimate();
-  uma_reporter_->AddBeginMainFrameToCommitDuration(
-      begin_main_frame_to_commit_duration, begin_main_frame_to_commit_estimate,
-      affects_estimate);
-  if (affects_estimate) {
+  if (enabled_) {
     begin_main_frame_to_commit_duration_history_.InsertSample(
         begin_main_frame_to_commit_duration);
   }
@@ -332,11 +318,9 @@ void CompositorTimingHistory::DidPrepareTiles() {
   DCHECK_NE(base::TimeTicks(), start_prepare_tiles_time_);
 
   base::TimeDelta prepare_tiles_duration = Now() - start_prepare_tiles_time_;
-
-  bool affects_estimate = AffectsEstimate();
   uma_reporter_->AddPrepareTilesDuration(
-      prepare_tiles_duration, PrepareTilesDurationEstimate(), affects_estimate);
-  if (affects_estimate)
+      prepare_tiles_duration, PrepareTilesDurationEstimate(), enabled_);
+  if (enabled_)
     prepare_tiles_duration_history_.InsertSample(prepare_tiles_duration);
 
   start_prepare_tiles_time_ = base::TimeTicks();
@@ -356,14 +340,12 @@ void CompositorTimingHistory::ReadyToActivate() {
 
   base::TimeDelta commit_to_ready_to_activate_estimate =
       CommitToReadyToActivateDurationEstimate();
+  uma_reporter_->AddCommitToReadyToActivateDuration(
+      time_since_commit, commit_to_ready_to_activate_estimate, enabled_);
   rendering_stats_instrumentation_->AddCommitToActivateDuration(
       time_since_commit, commit_to_ready_to_activate_estimate);
 
-  bool affects_estimate = AffectsEstimate();
-  uma_reporter_->AddCommitToReadyToActivateDuration(
-      time_since_commit, commit_to_ready_to_activate_estimate,
-      affects_estimate);
-  if (affects_estimate) {
+  if (enabled_) {
     commit_to_ready_to_activate_duration_history_.InsertSample(
         time_since_commit);
   }
@@ -380,10 +362,9 @@ void CompositorTimingHistory::DidActivate() {
   DCHECK_NE(base::TimeTicks(), start_activate_time_);
   base::TimeDelta activate_duration = Now() - start_activate_time_;
 
-  bool affects_estimate = AffectsEstimate();
-  uma_reporter_->AddActivateDuration(
-      activate_duration, ActivateDurationEstimate(), affects_estimate);
-  if (affects_estimate)
+  uma_reporter_->AddActivateDuration(activate_duration,
+                                     ActivateDurationEstimate(), enabled_);
+  if (enabled_)
     activate_duration_history_.InsertSample(activate_duration);
 
   start_activate_time_ = base::TimeTicks();
@@ -405,14 +386,11 @@ void CompositorTimingHistory::DidDraw() {
   rendering_stats_instrumentation_->AddDrawDuration(draw_duration,
                                                     draw_estimate);
 
-  bool affects_estimate = AffectsEstimate();
-  uma_reporter_->AddDrawDuration(draw_duration, draw_estimate,
-                                 affects_estimate);
-  if (affects_estimate)
-    draw_duration_history_.InsertSample(draw_duration);
+  uma_reporter_->AddDrawDuration(draw_duration, draw_estimate, enabled_);
 
-  if (draws_left_before_estimates_affected_ > 0)
-    draws_left_before_estimates_affected_--;
+  if (enabled_) {
+    draw_duration_history_.InsertSample(draw_duration);
+  }
 
   start_draw_time_ = base::TimeTicks();
 }