Adding UMA logging to touch text selection

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 1c84bd29ae3020f8fdac39c3610880b6ce974fbd..e341c0537d7311b1b0c8e3fa6eb6764dbc269884 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -7303,6 +7303,22 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="Event.TouchSelectionDuration" units="milliseconds">
+  <owner>mfomitchev@chromium.org</owner>
+  <summary>
+    The duration of touch selection sequence from the moment the text selection
+    handles are brought up, and until their dismissal.
+  </summary>
+</histogram>
+
+<histogram name="Event.TouchSelectionEndedWithAction" enum="BooleanEnabled">
+  <owner>mfomitchev@chromium.org</owner>
+  <summary>
+    Whether the touch selection sequence ended with the user selecting one of
+    the text manipulation actions, such as copy, cut, or paste. after startup).
+  </summary>
+</histogram>
+
 <histogram name="ExtensionActivity.AdInjected" units="Extension Count">
   <owner>felt@chromium.org</owner>
   <owner>rdevlin.cronin@chromium.org</owner>