Add timer to OffscreenCanvas's commit API

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 902520861305724d8bd489c342786cb902b6a933..a657e501296b5358001d5600bdfa4c2393be23ba 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.OffscreenCommitTimer" units="microseconds">
+  <owner>junov@chromium.org</owner>
+  <owner>xidachen@chromium.org</owner>
+  <summary>Wall clock durations of OffscreenCanvas.commit() calls.</summary>
+</histogram>
+
 <histogram name="Blink.Canvas.PutImageData" units="microseconds">
   <owner>junov@chromium.org</owner>
   <summary>Time spent on 2D canvas putImageData API call.</summary>
@@ -103164,6 +103170,18 @@ value.
   <affected-histogram name="Blink.Canvas.PutImageData"/>
 </histogram_suffixes>
 
+<histogram_suffixes name="BlinkCanvasOffscreenCommitType" separator=".">
+  <suffix name="GPUCanvasGPUCompositingMain"/>
+  <suffix name="GPUCanvasGPUCompositingWorker"/>
+  <suffix name="GPUCanvasSoftwareCompositingMain"/>
+  <suffix name="GPUCanvasSoftwareCompositingWorker"/>
+  <suffix name="SoftwareCanvasGPUCompositingMain"/>
+  <suffix name="SoftwareCanvasGPUCompositingWorker"/>
+  <suffix name="SoftwareCanvasSoftwareCompositingMain"/>
+  <suffix name="SoftwareCanvasSoftwareCompositingWorker"/>
+  <affected-histogram name="Blink.Canvas.OffscreenCommitTimer"/>
+</histogram_suffixes>
+
 <histogram_suffixes name="BlinkCanvasToBlobIdleEncodAndDelayType" separator=".">
   <suffix name="JPEG"/>
   <suffix name="PNG"/>