Report histogram creation results.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index b5facb3a68dc1b75d673410404dacf7b63c29e12..7a60fe4f9d0eed05ecd566d601660e4c62a9c70f 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -52982,6 +52982,15 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="UMA.Histogram.Activity" enum="HistogramActivityReport">
+  <owner>asvitkine@chromium.org</owner>
+  <owner>bcwhite@chromium.org</owner>
+  <summary>
+    Type and flags of every histogram created plus other activities. Counts are
+    not mutually-exclusive except for the different types.
+  </summary>
+</histogram>
+
 <histogram name="UMA.InitSequence" enum="UmaInitSequence">
   <owner>asvitkine@chromium.org</owner>
   <summary>
@@ -69155,6 +69164,20 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="2" label="Both devices, pointing and keyboard, detected."/>
 </enum>
 
+<enum name="HistogramActivityReport" type="int">
+  <int value="0" label="Reports created"/>
+  <int value="1" label="Histograms created"/>
+  <int value="2" label="Histograms found by look-up"/>
+  <int value="3" label="Logarithmic histograms created"/>
+  <int value="4" label="Linear histograms created"/>
+  <int value="5" label="Boolean histograms created"/>
+  <int value="6" label="Custom histograms created"/>
+  <int value="7" label="sparse histograms created"/>
+  <int value="8" label="UMA-targeted histograms created"/>
+  <int value="9" label="UMA-stability histograms created"/>
+  <int value="10" label="Persistent histograms created"/>
+</enum>
+
 <enum name="HistoryFaviconsRecoveryEnum" type="int">
   <summary>Error states noted in thumbnail_database.cc recovery code.</summary>
   <int value="0" label="RECOVERY_EVENT_RECOVERED">Successful recovery.</int>
@@ -87009,6 +87032,14 @@ To add a new entry, add it with any value and run test to compute valid value.
   <affected-histogram name="OOBE.StepCompletionTime"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="OtherActivityProcesses" separator="."
+    ordering="prefix">

[Alexei Svitkine (slow), 2016/03/07 21:14:51]

Actually, I think my preference would be for this to be a suffix, that way, it's
easy to add them all via UMA.Histogram.Activity* on the dashboard.

[bcwhite, 2016/03/07 22:20:41]

Done.

+  <suffix name="gpu-process"/>
+  <suffix name="renderer"/>
+  <suffix name="setup"/>
+  <affected-histogram name="UMA.Histogram.Activity"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="OverlappedReadImpact">
   <suffix name="OverlappedReadDisabled" label="Non-blocking reads"/>
   <suffix name="OverlappedReadEnabled" label="Default, async reads"/>