Added talkgadget blank page to trampoline triggers, pending server config changes.

remoting/webapp/me2mom/manifest.json

 {
   "name": "__MSG_PRODUCT_NAME_AND_VERSION__ NAME_SUFFIX",
   "version": "1.0.UNIQUE_VERSION",
   "description": "__MSG_PRODUCT_DESCRIPTION__",
   "default_locale": "en",
   "app": {
     "launch": {
       "local_path": "choice.html"
     }
   },
   "icons": {
     "128": "chromoting128.png",
     "16": "chromoting16.png"
   },
   "content_scripts": [
     {
       "matches": [
-      "https://chromoting-httpxmpp-oauth2-dev.corp.google.com/oauth2_trampoline",
-      "https://chromoting-httpxmpp-oauth2-dev.corp.google.com/oauth2_trampoline?*"
+          "https://chromoting-httpxmpp-oauth2-dev.corp.google.com/oauth2_trampoline",
+          "https://chromoting-httpxmpp-oauth2-dev.corp.google.com/oauth2_trampoline?*",
+          "https://talkgadget.google.com/talkgadget/blank",
+          "https://talkgadget.google.com/talkgadget/blank?*"
       ],
       "js": ["cs_oauth2_trampoline.js"]
     }
   ],
   "permissions": [
     "tabs",
     "https://accounts.google.com/o/oauth2/*",
     "https://www.google.com/accounts/*",
     "https://www.googleapis.com/chromoting/*"
   ],
   "PLUGINS": "PLACEHOLDER"
 }