Add "Keep chrome running in background" preference.

chrome/app/generated_resources.grd

 <?xml version="1.0" encoding="UTF-8"?>
 
 <!--
 This file contains definitions of resources that will be translated for each
 locale. OS values are passed through from Python's sys.platform:
 
   win32 - Windows
   darwin - Mac
   linux2 - Linux (both Views and GTK+)
 
@@ skipping 206 matching lines @@
       <message name="IDS_BACKGROUND_APP_INSTALLED_BALLOON_BODY" desc="The contents of the balloon that is displayed when a background app is installed">
         <ph name="APP_NAME">$1<ex>Background App</ex></ph> will launch at system startup and continue to run in the background even once you've closed all other <ph name="PRODUCT_NAME">$2<ex>Google Chrome</ex></ph> windows.
       </message>
       <message name="IDS_BACKGROUND_CRASHED_APP_BALLOON_MESSAGE" desc="The contents of the balloon that is displayed when a background app crashes">
         <ph name="APP_NAME">$1<ex>Background App</ex></ph> has crashed. Click this balloon to restart the app.
       </message>
       <message name="IDS_BACKGROUND_CRASHED_EXTENSION_BALLOON_MESSAGE" desc="The contents of the balloon that is displayed when an extension crashes">
         <ph name="APP_NAME">$1<ex>Extension</ex></ph> has crashed. Click this balloon to reload the extension.
       </message>
 
+      <message name="IDS_KEEP_CHROME_RUNNING_IN_BACKGROUND" desc="The checkbox in the status tray context menu that controls whether chrome keeps running in the background after the last window is closed">

[Rick Campbell, 2011/05/11 20:33:01]

Should probably be "Chromium" rather than "chrome"

[Andrew T Wilson (Slow), 2011/05/11 23:00:48]

Good point. I've broken this out into separate chrome/chromium strings.

+        Let <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph> Run In The Background
+      </message>
+
       <message name="IDS_SHOWFULLHISTORY_LINK" desc="The label of the Show Full History link at the bottom of the back/forward menu.">
         Show Full History
       </message>
 
       <message name="IDS_APPMENU_TOOLTIP" desc="The tooltip to show for the browser menu">
         Customize and control <ph name="PRODUCT_NAME">$1<ex>Google Chrome</ex></ph>
       </message>
 
       <message name="IDS_ALTERNATE_NAV_URL_VIEW_LABEL" desc="Label displayed in an infobar when a user searches for a term he may have meant to navigate to.">
         Did you mean to go to <ph name="SITE">$1<ex>http://intranetsite/</ex></ph>?
@@ skipping 8068 matching lines @@
       </message>
       <message name="IDS_OPTIONS_ADVANCED_SECTION_TITLE_NETWORK">
         Network
       </message>
       <message name="IDS_OPTIONS_ADVANCED_SECTION_TITLE_TRANSLATE">
         Translate
       </message>
       <message name="IDS_OPTIONS_ADVANCED_SECTION_TITLE_CLOUD_PRINT">
         <ph name="CLOUD_PRINT_NAME">Google Cloud Print</ph>
       </message>
+      <message name="IDS_OPTIONS_ADVANCED_SECTION_TITLE_BACKGROUND">
+        Background Apps
+      </message>
 
       <!-- Multiple download warning-->
       <message name="IDS_MULTI_DOWNLOAD_WARNING" desc="Warning invoked if multiple downloads are attempted without user interaction.">
         This site is attempting to download multiple files. Do you want to allow this?
       </message>
       <message name="IDS_MULTI_DOWNLOAD_WARNING_ALLOW" desc="Text on the allow button in the IDS_MULTI_DOWNLOAD_WARNING dialog">
         Allow
       </message>
       <message name="IDS_MULTI_DOWNLOAD_WARNING_DENY" desc="Text on the deny button in the IDS_MULTI_DOWNLOAD_WARNING dialog">
         Deny
@@ skipping 4026 matching lines @@
     </includes>
     <structures fallback_to_english="true">
       <structure name="IDD_CHROME_FRAME_FIND_DIALOG" file="cf_resources.rc" type="dialog" >
       </structure>
       <structure name="IDD_CHROME_FRAME_READY_PROMPT" file="cf_resources.rc" type="dialog" >
       </structure>
     </structures>
 
   </release>
 </grit>