Bug 907211 - Fix localized string access for download size. r=ally

browser/metro/components/HelperAppDialog.js

@@ -41,8 +41,10 @@ HelperAppLauncherDialog.prototype = {
     let displaySize = DownloadUtils.convertByteUnits(aSize);
     if (displaySize[0] > 0) // [0] is size, [1] is units
       return displaySize.join("");
-    else
-      return Strings.browser.GetStringFromName("downloadsUnknownSize");
+    else {
+      let browserBundle = Services.strings.createBundle("chrome://browser/locale/browser.properties");
+      return browserBundle.GetStringFromName("downloadsUnknownSize");
+    }
   },
 
   _getChromeWindow: function (aWindow) {