Bug 534944 - Avoid loading/importing weave files until necessary to speed up fennec startup

Have importing service.js trigger startup instead of only starting up from Weave.js, which now is used as a backup kickstarter. Only call import(service.js) when necessary from various Fennec files.

services/sync/Weave.js

@@ -59,8 +59,13 @@ WeaveService.prototype = {
       break;
 
     case "final-ui-startup":
-      Cu.import("resource://weave/service.js");
-      Weave.Service.onStartup();
+      // Force Weave service to load if it hasn't triggered from overlays
+      this.timer = Cc["@mozilla.org/timer;1"].createInstance(Ci.nsITimer);
+      this.timer.initWithCallback({
+        notify: function() {
+          Cu.import("resource://weave/service.js");
+        }
+      }, 10000, Ci.nsITimer.TYPE_ONE_SHOT);
       break;
     }
   }

services/sync/modules/service.js

@@ -253,8 +253,6 @@ WeaveSvc.prototype = {
         while (enum.hasMoreElements())
           wait += enum.getNext().gBrowser.mTabs.length;
         break;
-      case FENNEC_ID:
-        wait = 10;
     }
 
     // Make sure we wait a little but but not too long in the worst case
@@ -1523,3 +1521,6 @@ WeaveSvc.prototype = {
     }
   },
 };
+
+// Load Weave on the first time this file is loaded
+Weave.Service.onStartup();

services/sync/modules/util.js

@@ -795,6 +795,7 @@ let Utils = {
 
 let Svc = {};
 Svc.Prefs = new Preferences(PREFS_BRANCH);
+Svc.Obs = Observers;
 [["Annos", "@mozilla.org/browser/annotation-service;1", "nsIAnnotationService"],
  ["AppInfo", "@mozilla.org/xre/app-info;1", "nsIXULAppInfo"],
  ["Bookmark", "@mozilla.org/browser/nav-bookmarks-service;1", "nsINavBookmarksService"],