Media: Add improved duration histogram

media/base/pipeline_impl.cc

Index: media/base/pipeline_impl.cc
diff --git a/media/base/pipeline_impl.cc b/media/base/pipeline_impl.cc
index f8761f4c725a3c3a7a444c381a5dac7bf6f6ab14..ca2a84597344df051938d4530617c4b87caa679a 100644
--- a/media/base/pipeline_impl.cc
+++ b/media/base/pipeline_impl.cc
@@ -505,7 +505,9 @@ void PipelineImpl::RendererWrapper::SetDuration(base::TimeDelta duration) {
   // implementations call DemuxerHost on the media thread.
   media_log_->AddEvent(media_log_->CreateTimeEvent(MediaLogEvent::DURATION_SET,
                                                    "duration", duration));
-  UMA_HISTOGRAM_LONG_TIMES("Media.Duration", duration);
+  UMA_HISTOGRAM_CUSTOM_TIMES(
+      "Media.Duration2", duration, base::TimeDelta::FromMilliseconds(1),
+      base::TimeDelta::FromDays(1), 100 /* bucket_count */);

[Alexei Svitkine (slow), 2017/03/03 16:37:37]

Are you sure you really need more buckets and not just a higher maximum range?

We generally advise against more than 50 buckets because it's often not needed
and results in increased data use for UMA histograms.

[johnme, 2017/03/03 18:58:05]

We can probably get by with fewer. I've updated the patch to only use 50 buckets
- that means the buckets are now powers of 1.452, whereas before this patch they
were powers of 1.361.

Dale, are you ok with that? Some alternatives include:
- 24h max 60 buckets -> 1.363
- 12h max 50 buckets -> 1.432
- 6h max 50 buckets -> 1.412

 
   main_task_runner_->PostTask(
       FROM_HERE,