Report histogram creation results.

base/metrics/statistics_recorder.cc

Index: base/metrics/statistics_recorder.cc
diff --git a/base/metrics/statistics_recorder.cc b/base/metrics/statistics_recorder.cc
index d0fa2add3603b3f574dfa9ef9e5ee2e6b152aafc..5f7c4e406bd1ba47fdf8a3512c9604f0cf9babef 100644
--- a/base/metrics/statistics_recorder.cc
+++ b/base/metrics/statistics_recorder.cc
@@ -369,6 +369,17 @@ StatisticsRecorder::OnSampleCallback StatisticsRecorder::FindCallback(
 }
 
 // static
+size_t StatisticsRecorder::NumberOfHistograms() {

[Alexei Svitkine (slow), 2016/03/01 16:41:34]

Nit: GetHistogramCount()

[bcwhite, 2016/03/02 19:14:19]

Done.

+  if (!lock_)
+    return 0;
+
+  base::AutoLock auto_lock(*lock_);
+  if (!histograms_)
+    return 0;
+  return histograms_->size();
+}
+
+// static
 void StatisticsRecorder::ResetForTesting() {
   // Just call the private version that is used also by the destructor.
   Reset();