Add display scaling and rotation shortcuts to keyboard overlay.

chrome/app/chromeos_strings.grdp

 <?xml version="1.0" encoding="utf-8"?>
 <!-- ChromeOS-specific strings (included from generated_resources.grd).
      Everything in this file is wrapped in <if expr="pp_ifdef('chromeos')">. -->
 <grit-part>
   <!-- Idle logout dialog for retail mode -->
   <message name="IDS_IDLE_LOGOUT_TITLE" desc="Dialog title for the idle logout dialog. Used in retail mode only.">
     Are you still there?
   </message>
   <message name="IDS_IDLE_LOGOUT_WARNING_RESTART" desc="Restart label for the idle logout dialog. Used in retail mode only..">
     This computer will reset in <ph name="LOGOUT_TIME_LEFT">$1<ex>20</ex></ph> seconds.
@@ skipping 2972 matching lines @@
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_RELOAD_IGNORING_CACHE" desc="The text in the keyboard overlay to explain the shortcut.">
     Reload ignoring cache
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_REOPEN_LAST_CLOSED_TAB" desc="The text in the keyboard overlay to explain the shortcut.">
     Reopen last-closed tab
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_REPORT_ISSUE" desc="The text in the keyboard overlay to explain the shortcut (report an issue).">
     Report issue
   </message>
+  <message name="IDS_KEYBOARD_OVERLAY_RESET_SCREEN_ZOOM" desc="The text in the keyboard overlay to explain the shortcut (reset the screen zoom).">
+    Reset screen zoom
+  </message>
   <message name="IDS_KEYBOARD_OVERLAY_RESET_ZOOM" desc="The text in the keyboard overlay to explain the shortcut.">
     Reset zoom
   </message>
+  <message name="IDS_KEYBOARD_OVERLAY_ROTATE_SCREEN" desc="The text in the keyboard overlay to explain the shortcut (rotate the screen).">
+    Rotate screen
+  </message>
   <message name="IDS_KEYBOARD_OVERLAY_SAVE" desc="The text in the keyboard overlay to explain the shortcut (save page as a file).">
     Save
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_SCREENSHOT_REGION" desc="The text in the keyboard overlay to explain the shortcut (take a screenshot of the selected region).">
     Screenshot region
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_SCROLL_UP_ONE_PAGE" desc="The text in the keyboard overlay to explain the shortcut.">
     Scroll up one page
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_SELECT_ALL" desc="The text in the keyboard overlay to explain the shortcut.">
@@ skipping 46 matching lines @@
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_WORD_MOVE" desc="The text in the keyboard overlay to explain the shortcut.">
     Word move
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_ZOOM_IN" desc="The text in the keyboard overlay to explain the shortcut.">
     Zoom in
   </message>
   <message name="IDS_KEYBOARD_OVERLAY_ZOOM_OUT" desc="The text in the keyboard overlay to explain the shortcut.">
     Zoom out
   </message>
+  <message name="IDS_KEYBOARD_OVERLAY_ZOOM_SCREEN_IN" desc="The text in the keyboard overlay to explain the shortcut (zoom in the screen).">
+    Zoom screen in
+  </message>
+  <message name="IDS_KEYBOARD_OVERLAY_ZOOM_SCREEN_OUT" desc="The text in the keyboard overlay to explain the shortcut (zoom out the screen).">
+    Zoom screen out
+  </message>
   <!-- END GENERATED KEYBOARD OVERLAY STRINGS -->
   <if expr="lang == 'ja'">
     <message name="IDS_STATUSBAR_IME_JAPANESE_IME_STATUS_HIRAGANA" desc="In the language menu button, this shows a character set in use is set to Hiragana.">
       Hiragana
     </message>
     <message name="IDS_STATUSBAR_IME_JAPANESE_IME_STATUS_KATAKANA" desc="In the language menu button, this shows a character set in use is set to KATAKANA.">
       Katakana
     </message>
   </if>
   <if expr="lang != 'ja'">
@@ skipping 501 matching lines @@
   <message name="IDS_KIOSK_APP_ERROR_UNABLE_TO_MOUNT" desc="Error message used when a kiosk app fails to launch due to cryptohome error.">
     Kryptonite! The cryptohome for the kiosk application could not be mounted.
   </message>
   <message name="IDS_KIOSK_APP_ERROR_UNABLE_TO_INSTALL" desc="Error message used when a kiosk app fails to launch due to install failure.">
     Kiosk application could not be installed.
   </message>
   <message name="IDS_KIOSK_APP_ERROR_USER_CANCEL" desc="Error message used when a kiosk app launch is canceled by user.">
     Kiosk application launch canceled.
   </message>
 </grit-part>