Record histograms for timing information in DomDistiller.

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 8321fe938ca8b6b30f954385cee757219bb4be5c..8aa41c3aa6330fe76eceef7b57d1733c560bab6f 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -4998,6 +4998,13 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <summary>Whether a Domain Reliability upload succeeded.</summary>
 </histogram>
 
+<histogram name="DomDistiller.ArticleProcessingTime" units="milliseconds">
+  <owner>yfriedman@chromium.org</owner>
+  <summary>
+    Time spent in DomDistiller's identification of text content.
+  </summary>
+</histogram>
+
 <histogram name="DomDistiller.DistillationQuality" enum="BooleanSuccess">
   <owner>nyquist@chromium.org</owner>
   <summary>
@@ -5005,6 +5012,41 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="DomDistiller.DistillationTotalTime" units="milliseconds">
+  <owner>yfriedman@chromium.org</owner>
+  <summary>Complete time spent in DomDistiller's processing of a page.</summary>
+</histogram>
+
+<histogram name="DomDistiller.DocumentConstructionTime" units="milliseconds">
+  <owner>yfriedman@chromium.org</owner>
+  <summary>
+    Time spent in creating DomDistiller's internal representation of the HTML
+    document.
+  </summary>
+</histogram>
+
+<histogram name="DomDistiller.FormattingTime" units="milliseconds">
+  <owner>yfriedman@chromium.org</owner>
+  <summary>
+    Time spent in DomDistiller's final processing of article content/formatting.
+  </summary>
+</histogram>
+
+<histogram name="DomDistiller.MarkupParsingTime" units="milliseconds">

[Ilya Sherman, 2014/08/27 22:12:08]

Optional: You might want to name this histograms as "DomDistiller.Time.Foo", so
that they are alphabetically sorted together.

[Yaron, 2014/08/27 23:12:26]

I like it. Done.

+  <owner>yfriedman@chromium.org</owner>
+  <summary>
+    Time spent in DomDistiller's processing of article metadata.
+  </summary>
+</histogram>
+
+<histogram name="DomDistiller.PageDistillable" enum="BooleanAvailable">

[Ilya Sherman, 2014/08/27 22:12:08]

Even better than using BooleanAvailable would be to define a custom enum, with
buckets labelled something like "Distillable" and "Not distillable".  (Note:
This comment applies just to the histograms.xml file, no changes needed
elsewhere).

[Yaron, 2014/08/27 23:12:26]

Done.

+  <owner>yfriedman@chromium.org</owner>
+  <summary>
+    Records the number of times a page was loaded for which using DomDistiller
+    is possible.
+  </summary>
+</histogram>
+
 <histogram name="Download.AcceptRangesBytes.KBytes" units="KB">
   <owner>asanka@chromium.org</owner>
   <summary>The length of downloads for serves that accept byte ranges.</summary>