Record how often we end up in Chrome from external navigations.

tools/metrics/actions/actions.xml

 <!--
 Copyright 2014 The Chromium Authors. All rights reserved.
 Use of this source code is governed by a BSD-style license that can be
 found in the LICENSE file.
 -->
 
 <!--
 This file is a comprehensive list of Chrome user actions along with the owner
 and description for each user action. A user action should be tied to an actual
 action taken by a user. It should be logged immediately after a user takes the
@@ skipping 8706 matching lines @@
   <description>Please enter the description of this user action.</description>
   <obsolete>Deprecated as of 8/2015</obsolete>
 </action>
 
 <action name="MobileContextMenuViewImage">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
   <obsolete>Deprecated as of 8/2015</obsolete>
 </action>
 
+<action name="MobileExternalNavigationReceived">

[Ilya Sherman, 2016/06/28 21:50:55]

You mentioned there was a parallel user action already in place.  What is the
name of that action, and would it make sense to name this action in parallel to
it?

[Maria, 2016/06/28 23:00:26]

It's actually a histogram called Android.TabNavigationInterceptResult.

[Ilya Sherman, 2016/06/29 20:21:15]

Ah.  It's a bit hard to compare user actions and histograms, as they're not
recorded in exactly the same way.  For example, there are differences in terms
of which metrics are recorded in Incognito mode.  I'd recommend recording any
metrics that you wish to compare using the same underlying mechanism. 
Otherwise, you'll need to make various affordances to be able to actually
compare the data.

+  <owner>mariakhomenko@chromium.org</owner>
+  <description>
+    Records  when a user was given a choice between using Chrome and a system
+    app and chose Chrome.
+  </description>
+</action>
+
 <action name="MobileFirstEditInOmnibox">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
   <obsolete>Deprecated as of 12/2015</obsolete>
 </action>
 
 <action name="MobileFocusedFakeboxOnNtp">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
   <obsolete>Deprecated as of 12/2015</obsolete>
@@ skipping 6103 matching lines @@
 <action name="webapps.AddShortcut.Manifest">
   <owner>mlamouri@chromium.org</owner>
   <description>
     Shortcut added to the homescreen with a valid Manifest. This action will be
     recorded in addition to AppShortcut, AppShortcutApple and Bookmark actions
     to keep a trend of whether the webapp also add meta tags.
   </description>
 </action>
 
 </actions>