Added UMA stat for tracking accidental navigations on double tap.

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 495308e9964c327e73ef6e5472a16ed10ed8e36a..7492e1e88fff140b73dce62bdf3586480b13c53c 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -18860,6 +18860,26 @@ other types of suffix sets.
   </summary>
 </histogram>
 
+<histogram name="UserInput.ActionAfterDoubleTapNoDelay"
+    enum="ActionAfterDoubleTap">
+  <summary>
+    User's first action within 5 seconds after a double tap gesture when gesture
+    tap event delay is disabled.
+  </summary>
+</histogram>
+
+<histogram name="UserInput.ActionAfterDoubleTapWithDelay"
+    enum="ActionAfterDoubleTap">
+  <summary>
+    User's first action within 5 seconds after a double tap gesture when gesture
+    tap events are delayed.
+  </summary>
+</histogram>
+
+<histogram name="UserInput.SingleTapType" enum="TapDelayType">
+  <summary>The number of gesture taps that are delayed vs undelayed</summary>
+</histogram>
+
 <histogram name="UserManager.LoginUserType" enum="UserType">
   <summary>
     The number of users of different types that log in to the system (Chrome
@@ -19794,6 +19814,12 @@ other types of suffix sets.
   <int value="2" label="ScrolledMainFrameWithUnacceleratedFixedRootBackground"/>
 </enum>
 
+<enum name="ActionAfterDoubleTap" type="int">
+  <int value="0" label="Navigated Back"/>
+  <int value="1" label="Stopped Navigation"/>
+  <int value="2" label="No Action"/>
+</enum>
+
 <enum name="ActionUponResourceRequest" type="int">
   <int value="0" label="Load resource"/>
   <int value="1" label="Revalidate resource"/>
@@ -28062,6 +28088,11 @@ other types of suffix sets.
   <int value="1" label="Revisit"/>
 </enum>
 
+<enum name="TapDelayType" type="int">
+  <int value="0" label="Delayed Tap"/>
+  <int value="1" label="Undelayed Tap"/>
+</enum>
+
 <enum name="TcpSocketStatus" type="int">
   <int value="0" label="Unknown"/>
   <int value="1" label="Fast Connection Return"/>