[iOS] Add Request Mobile Site cell to tools menu

ios/chrome/app/strings/ios_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!--
 This file contains definition of resources that will be translated for each
 locale.  The strings in this file are specific to iOS.
 -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       output_all_resource_defines="false" source_lang_id="en" enc_check="möl">
   <outputs>
@@ skipping 1450 matching lines @@
       </message>
       <message name="IDS_IOS_TOOLS_MENU_READING_LIST" desc="The iOS menu item for opening the reading list [Length: 15em] [iOS only]">
         Reading List
       </message>
       <message name="IDS_IOS_TOOLS_MENU_RECENT_TABS" desc="The iOS menu item for opening the panel showing the recently closed tabs and the tabs from other devices. [Length: 15em] [iOS only]">
         Recent Tabs
       </message>
       <message name="IDS_IOS_TOOLS_MENU_REQUEST_DESKTOP_SITE" desc="The iOS menu item for requesting the desktop site [Length: 15em] [iOS only]">
         Request Desktop Site
       </message>
+      <message name="IDS_IOS_TOOLS_MENU_REQUEST_MOBILE_SITE" desc="The iOS menu item for requesting the mobile site [Length: 15em] [iOS only]">

[srahim, 2017/04/07 00:15:07]

Per localization, please increase the character limit for this message to 25
characters.

+        Request Mobile Site
+      </message>
       <message name="IDS_IOS_TOOLS_MENU_SETTINGS" desc="The iOS menu item for opening the settings [Length: 15em] [iOS only]">
         Settings
       </message>
       <message name="IDS_IOS_TOOLS_MENU_SHARE" desc="The iOS menu item for sharing the current URL [Length: 15em] [iOS only]">
         Share...
       </message>
       <message name="IDS_IOS_TOOLS_MENU_SUGGESTIONS" desc="The iOS menu item for displaying the Suggestions UI [Length: 15em] [iOS only]">
         Suggestions
       </message>
       <message name="IDS_IOS_TRANSLATE_SETTING" desc="Title for the view and option in Settings for Translate. [Length: 25em] [iOS only]">
@@ skipping 22 matching lines @@
       </message>
       <message name="IDS_IOS_VOICE_SEARCH_SETTING_TITLE" desc="The title for Voice Search setting [Length: 29em] [iOS only]">
         Voice Search
       </message>
       <message name="IDS_IOS_VOICE_SEARCH_SETTING_TTS" desc="The label for setting switch enabling text-to-speech response after voice search [Length: 29em] [iOS only]">
         Speak Answers Back
       </message>
     </messages>
   </release>
 </grit>