Final pass at removing unused strings.

app/resources/app_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 163 matching lines @@
     <file path="app_strings_te.xtb" lang="te" />
     <file path="app_strings_th.xtb" lang="th" />
     <file path="app_strings_tr.xtb" lang="tr" />
     <file path="app_strings_uk.xtb" lang="uk" />
     <file path="app_strings_vi.xtb" lang="vi" />
     <file path="app_strings_zh-CN.xtb" lang="zh-CN" />
     <file path="app_strings_zh-TW.xtb" lang="zh-TW" />
   </translations>
   <release seq="1" allow_pseudo="false">
     <messages fallback_to_english="true">
-    
+
       <!-- Menus -->
       <message name="IDS_APP_MENU_EMPTY_SUBMENU" desc="Used when a submenu has no entries">
         (empty)
       </message>
 
       <!-- General application strings -->
       <message name="IDS_APP_UNTITLED_SHORTCUT_FILE_NAME" desc="The name of the Internet Shortcut file created for URLs dragged that have no title">
         Untitled Web Page
       </message>
       <message name="IDS_APP_SAVEAS_ALL_FILES" desc="Save As dialog box default text">
@@ skipping 139 matching lines @@
       <!-- Shortcut Modifiers -->
       <message name="IDS_APP_CONTROL_MODIFIER" desc="Control key shortcut modifier">
         Ctrl+<ph name="KEY_COMBO_NAME">$1<ex>C</ex></ph>
       </message>
       <message name="IDS_APP_ALT_MODIFIER" desc="Alt key shortcut modifier">
         Alt+<ph name="KEY_COMBO_NAME">$1<ex>C</ex></ph>
       </message>
       <message name="IDS_APP_SHIFT_MODIFIER" desc="Shift key shortcut modifier">
         Shift+<ph name="KEY_COMBO_NAME">$1<ex>C</ex></ph>
       </message>
-      
     </messages>
   </release>
 </grit>