Introduce user customization of external HighDPI mode for 4K monitor.

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 8331 matching lines @@
   <description>Settings: Device: Display settings</description>
 </action>
 
 <action name="Options_DisplayRearrange">
   <owner>stevenjb@chromium.org</owner>
   <description>
     Settings: Device: Display settings: arrange desktops
   </description>
 </action>
 
+<action name="Options_DisplaySetMode">
+  <owner>stevenjb@chromium.org</owner>
+  <description>
+    Settings: Device: Display settings: Display mode (i.e. resolution, UI-scale,
+    and device scale factor).
+  </description>
+</action>

[stevenjb, 2014/07/30 17:49:59]

I don't think we actually need to rename this, just update the comment.

[Jun Mukai, 2014/07/30 23:50:51]

Done.

+
 <action name="Options_DisplaySetOrientation">
   <owner>stevenjb@chromium.org</owner>
   <description>Settings: Device: Display settings: Orientation</description>
 </action>
 
 <action name="Options_DisplaySetPrimary">
   <owner>stevenjb@chromium.org</owner>
   <description>Settings: Device: Display settings: Make primary</description>
 </action>
 
-<action name="Options_DisplaySetResolution">
-  <owner>stevenjb@chromium.org</owner>
-  <description>Settings: Device: Display settings: Resolution</description>
-</action>
-
 <action name="Options_DisplayToggleMirroring">
   <owner>stevenjb@chromium.org</owner>
   <description>Settings: Device: Display settings: Start mirroring</description>
 </action>
 
 <action name="Options_DnsPrefetchCheckbox_Disable">
   <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 3018 matching lines @@
   <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="webapps.AddShortcut.Bookmark">
   <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>
 
 </actions>