Implemented new channel switcher UI.

chrome/app/google_chrome_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This file contains definitions of strings that are specific to
 Google Chrome. These strings will be translated for each locale that Google
 Chrome supports. -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       source_lang_id="en" enc_check="möl">
   <outputs>
     <output filename="grit/google_chrome_strings.h" type="rc_header">
       <emit emit_type='prepend'></emit>
@@ skipping 630 matching lines @@
       <if expr="not pp_ifdef('chromeos')">
         <message name="IDS_UPGRADE_SUCCESSFUL_RELAUNCH" desc="Status label: Successfully updated Google Chrome">
           Nearly up-to-date! Relaunch Google Chrome to finish updating.
         </message>
       </if>
       <if expr="pp_ifdef('chromeos')">
         <message name="IDS_UPGRADE_SUCCESSFUL_RELAUNCH" desc="Status label: Successfully updated Chrome OS">
           Nearly up-to-date! Restart your device to finish updating.
         </message>
       </if>
+      <if expr="pp_ifdef('chromeos')">
+        <message name="IDS_UPGRADE_SUCCESSFUL_CHANNEL_SWITCH" desc="Status label: Channel was successfully switched on Chrome OS">
+          Channel changed. Restart your device to apply changes.
+        </message>
+      </if>
       <if expr="not pp_ifdef('chromeos')">
         <message name="IDS_UPGRADE_UP_TO_DATE" desc="Status label: Already up to date (Google Chrome)">
           Google Chrome is up to date.
         </message>
       </if>
       <if expr="pp_ifdef('chromeos')">
         <message name="IDS_UPGRADE_UP_TO_DATE" desc="Status label: Already up to date (Chrome OS)">
           Your device is up to date.
         </message>
       </if>
       <if expr="not pp_ifdef('chromeos')">
         <message name="IDS_UPGRADE_UPDATING" desc="Status label: Updating Google Chrome">
           Updating Google Chrome...
         </message>
       </if>
       <if expr="pp_ifdef('chromeos')">
         <message name="IDS_UPGRADE_UPDATING" desc="Status label: Updating Chrome OS">
           Updating your device...
         </message>
       </if>
+      <if expr="pp_ifdef('chromeos')">
+        <message name="IDS_UPGRADE_UPDATING_CHANNEL_SWITCH" desc="Status label: Updating Chrome OS to a specified channel">
+          Updating your device to <ph name="CHANNEL_NAME">$1<ex>stable</ex></ph> channel...
+        </message>
+      </if>
 
       <!-- iOS Upgrade available info bar-->
       <if expr="pp_ifdef('ios')">
         <message name="IDS_UPGRADE_AVAILABLE" desc="Text to inform the user of the presence of a new version of the application">
           Chrome just got better! A new version is available.
         </message>
         <message name="IDS_UPGRADE_AVAILABLE_BUTTON" desc="Diplayed on a button the user can use to upgrade the a more recent version of the application. [Length: 10em]">
           Update
         </message>
       </if>
@@ skipping 235 matching lines @@
         <message name="IDS_MESSAGE_CENTER_BALLOON_TITLE" desc="Title of the first run notification ballon describing the notification center.">
           Chrome Notification Center
         </message>
         <message name="IDS_MESSAGE_CENTER_BALLOON_TEXT" desc="Body text for the the first run notification ballon describing the notification center.">
           You can see all your notifications from Chrome apps, extensions, and websites here.
         </message>
       </if>
     </messages>
   </release>
 </grit>