Adds histograms for casting feature of Video Player

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.
 
@@ skipping 11357 matching lines @@
   <description>Please enter the description of this user action.</description>
   <obsolete>Removed from codebase; see GoogleUpdate.UpgradeResult.</obsolete>
 </action>
 
 <action name="Upgrade_Started">
   <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>Removed from codebase; see GoogleUpdate.UpgradeResult.</obsolete>
 </action>
 
+<action name="VideoPlayer.NumberOfCastDevice">
+  <owner>yoshiki@chromium.org</owner>
+  <description>Chrome OS Video Player: the number of cast devices.</description>
+</action>

[Ilya Sherman, 2014/12/09 01:57:48]

This sounds like it should be a histogram rather than an action.  What does "the
number of cast devices" mean as aan action?

[yoshiki, 2014/12/10 03:20:50]

Sorry, that was my mistake. I added NumberOfCastDevice instead of CastVideoError
by mistake.

+
+<action name="VideoPlayer.OpenVideoPlayer">
+  <owner>yoshiki@chromium.org</owner>
+  <description>
+    Chrome OS Video Player: this is recorded when user opens video player.

[Ilya Sherman, 2014/12/09 01:57:48]

Optional nit: I'd rephrase slightly as: "The user opened the Chrome OS Video
Player".

[yoshiki, 2014/12/10 03:20:50]

Thanks for guidance! Done.

+  </description>
+</action>
+
 <action name="ViewAboutConflicts">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
 </action>
 
 <action name="ViewAboutFlash">
   <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
   <description>Please enter the description of this user action.</description>
 </action>
 
@@ skipping 394 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>