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 502f97d51c27ef34d5feda8a9f310394693dad50..ba842101d526d80b8e857d5efe119a4ba4fc961c 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -3956,6 +3956,12 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <summary>Time spent on 2D canvas getImageData API call.</summary>
 </histogram>
 
+<histogram name="Blink.Canvas.OffscreenCommit" units="microseconds">

[Ilya Sherman, 2016/10/12 22:19:09]

nit: I'd suggest appending "Time" to the end of this metric name, for clarity.

[xidachen, 2016/10/13 01:39:24]

Done.

+  <owner>junov@chromium.org</owner>
+  <owner>xidachen@chromium.org</owner>
+  <summary>Time spent on OffscreenCanvas's commit before compositing.</summary>

[Justin Novosad, 2016/10/12 21:11:12]

This is Unclear IMHO. I believe a more accurate description would be: Wall clock
durations of OffscreenCanvas.commit() calls

[xidachen, 2016/10/13 01:39:24]

Done.

+</histogram>
+
 <histogram name="Blink.Canvas.PutImageData" units="microseconds">
   <owner>junov@chromium.org</owner>
   <summary>Time spent on 2D canvas putImageData API call.</summary>
@@ -103064,6 +103070,14 @@ value.
   <affected-histogram name="Blink.Canvas.PutImageData"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="BlinkCanvasOffscreenCommitType" separator=".">
+  <suffix name="GPUCanvasGPUCompositing"/>
+  <suffix name="GPUCanvasSoftwareCompositing"/>
+  <suffix name="SoftwareCanvasGPUCompositing"/>
+  <suffix name="SoftwareCanvasSoftwareCompositing"/>
+  <affected-histogram name="Blink.Canvas.OffscreenCommit"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="BlinkCanvasToBlobIdleEncodAndDelayType" separator=".">
   <suffix name="JPEG"/>
   <suffix name="PNG"/>