Make flags resources naming consistent

chrome/app/chromium_strings.grd

 <?xml version="1.0" encoding="UTF-8"?>
 <!-- This file contains definitions of strings that are distribution specific.
 If you update this file, be sure also to update google_chrome_strings.grd. -->
 
 <grit base_dir="." latest_public_release="0" current_release="1"
       output_all_resource_defines="false" source_lang_id="en" enc_check="möl">
   <outputs>
     <output filename="grit/chromium_strings.h" type="rc_header">
       <emit emit_type='prepend'></emit>
     </output>
@@ skipping 520 matching lines @@
         other {# downloads are currently in progress. Do you want to cancel the downloads and exit Chromium?}}
       </message>
 
       <!-- Quit all apps confirmation dialog -->
       <if expr="is_macosx">
         <message name="IDS_QUIT_WITH_APPS_TITLE" desc="Title for a notification explaining that Chrome is running in the background.">
           Chromium is in background mode.
         </message>
       </if>
 
-      <!-- about:flags -->
-      <message name="IDS_FLAGS_DEBUG_SHORTCUTS_DESCRIPTION" desc="Description of the 'Debugging keyboard shortcuts' lab.">
-        Enables additional keyboard shortcuts that are useful for debugging Chromium.
-      </message>
-
       <!-- Obsolete System info bar -->
       <message name="IDS_SYSTEM_OBSOLETE_MESSAGE" desc="Message shown when your OS is no longer supported. This message is followed by a 'Learn more' link.">
          Chromium has stopped updating and no longer supports this version of your operating system.
       </message>
 
       <!-- Google API keys info bar -->
       <message name="IDS_MISSING_GOOGLE_API_KEYS" desc="Message shown when Google API keys are missing. This message is followed by a 'Learn more' link.">
         Google API keys are missing. Some functionality of Chromium will be disabled.
       </message>
 
@@ skipping 695 matching lines @@
         <message name="IDS_WIN10_WELCOME_PIN_SUBHEADING" desc="A subheading on a section which gives instructions on how to pin Chromium to the Windows 10 taskbar.">
           Pin Chromium to your taskbar
         </message>
         <message name="IDS_WIN10_WELCOME_SELECT" desc="An instruction asking the user to select Chromium from an external list of apps.">
           Select <ph name="SMALL_PRODUCT_LOGO">&lt;div class="logo-small"&gt;&lt;/div&gt;</ph> <ph name="BEGIN_BOLD">&lt;strong&gt;</ph>Chromium<ph name="END_BOLD">&lt;/strong&gt;</ph>
         </message>
       </if>
     </messages>
   </release>
 </grit>