Launcher Search box, Back and Mic buttons now focusable in ChromeVox.

ui/strings/ui_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!-- This file contains definitions of resources that will be translated for
 each locale. Specifically, these are UI strings that are used by app/ that
 need to be translated for each locale.-->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       source_lang_id="en" enc_check="möl">
   <outputs>
     <!-- TODO add each of your output files.  Modify the three below, and add
@@ skipping 2163 matching lines @@
       <!-- App list -->
       <message name="IDS_APP_LIST_HELP" desc="The menu entry to show the app list help UI.">
         Help
       </message>
       <message name="IDS_APP_LIST_OPEN_SETTINGS" desc="The menu entry to show the settings UI.">
         Settings
       </message>
       <message name="IDS_APP_LIST_OPEN_FEEDBACK" desc="The menu entry to show the feedback UI.">
         Send feedback
       </message>
+      <message name="IDS_APP_LIST_BACK" desc="The name of the button that goes to the previous screen in the launcher.">
+        Back
+      </message>
       <message name="IDS_APP_LIST_ALL_APPS" desc="The text on the button that opens the app grid view in the app launcher.">
         All Apps
       </message>
       <message name="IDS_APP_LIST_FOLDER_NAME_PLACEHOLDER" desc="The placeholder text for app list folder name.">
         Unnamed Folder
       </message>
       <message name="IDS_APP_LIST_FOLDER_BUTTON_ACCESSIBILE_NAME" desc="The spoken feedback text for navigating to a folder button in top level app list">
         Folder <ph name="folder_name">$1<ex>OEM Apps</ex></ph>
       </message>
       <message name="IDS_APP_LIST_FOLDER_OPEN_FOLDER_ACCESSIBILE_NAME" desc="The spoken feedback text for opening an app launcher folder">
         Open folder
       </message>
       <message name="IDS_APP_LIST_FOLDER_CLOSE_FOLDER_ACCESSIBILE_NAME" desc="The spoken feedback text for closing an app launcher folder">
         Close folder
       </message>
       <message name="IDS_APP_LIST_SPEECH_HINT_TEXT" desc="The text label in the speech recognition UI to ask the user to speak the search query">
         Speak now
       </message>
       <message name="IDS_APP_LIST_SPEECH_NETWORK_ERROR_HINT_TEXT" desc="The text label in the speech recognition UI to show the speech recognition can't start because of network error.">
         No internet connection
       </message>
     </messages>
   </release>
 </grit>