Revert "Surface synchronization: Don't report blocked duration of throttled children"

This reverts commit d15ba9ba.

Reason for revert: This doesn't seem to solve the deadline reporting bug. This was a speculative fix that didn't fix the issue.

Original change's description:
> Surface synchronization: Don't report blocked duration of throttled children
> 
> A child can be "throttled" for an arbitrary length of time if it is never
> embedded. This skews blocked duration metrics. Simply don't report those
> metrics if a surface is blocked on a parent.
> 
> Bug: 890767
> Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel
> Change-Id: I3c8a8494a5b1e5a973b2e5c2b61cffe5c2b76f6f
> Reviewed-on: https://chromium-review.googlesource.com/c/1274591
> Commit-Queue: Fady Samuel <fsamuel@chromium.org>
> Reviewed-by: Saman Sami <samans@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#598886}

TBR=fsamuel@chromium.org,samans@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: 890767
Change-Id: I3b1188d49a1301681391d526abaa25dcabf69f79
Cq-Include-Trybots: luci.chromium.try:android_optional_gpu_tests_rel
Reviewed-on: https://chromium-review.googlesource.com/c/1281083Reviewed-by: Fady Samuel <fsamuel@chromium.org>
Commit-Queue: Fady Samuel <fsamuel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#599716}

components/viz/service/surfaces/surface.cc

@@ -198,11 +198,6 @@ void Surface::OnSurfaceDependencyAdded() {
 
   DCHECK(frame_sink_id_dependencies_.empty());
 
-  // Cancel the deadline and don't report UMA. The UMA metrics are only
-  // meaningful for activation dependencies and not throttling.
-  deadline_->CancelWithoutReport();
-  DCHECK(!deadline_->has_deadline());
-
   // All blockers have been cleared. The surface can be activated now.
   ActivatePendingFrame(base::nullopt);
 }

components/viz/service/surfaces/surface_dependency_deadline.cc

@@ -41,13 +41,6 @@ base::Optional<base::TimeDelta> SurfaceDependencyDeadline::Cancel() {
   return CancelInternal(false);
 }
 
-void SurfaceDependencyDeadline::CancelWithoutReport() {
-  if (!deadline_)
-    return;
-  begin_frame_source_->RemoveObserver(this);
-  deadline_.reset();
-}
-
 void SurfaceDependencyDeadline::InheritFrom(
     const SurfaceDependencyDeadline& other) {
   if (*this == other)
@@ -103,7 +96,8 @@ base::Optional<base::TimeDelta> SurfaceDependencyDeadline::CancelInternal(
   if (!deadline_)
     return base::nullopt;
 
-  CancelWithoutReport();
+  begin_frame_source_->RemoveObserver(this);
+  deadline_.reset();
 
   base::TimeDelta duration = tick_clock_->NowTicks() - start_time_;
 

components/viz/service/surfaces/surface_dependency_deadline.h

@@ -36,12 +36,6 @@ class VIZ_SERVICE_EXPORT SurfaceDependencyDeadline : public BeginFrameObserver {
   // deadline set, then return base::nullopt.
   base::Optional<base::TimeDelta> Cancel();
 
-  // If a deadline had been set, then cancel the deadline and don't
-  // generate a UMA report. When a surface activation has been throttled
-  // then the time to activation could be arbitrarily delayed and may
-  // skew metrics.
-  void CancelWithoutReport();
-
   bool has_deadline() const { return deadline_.has_value(); }
 
   base::Optional<base::TimeTicks> deadline_for_testing() const {