Bug 747451 - Desktop web runtime user agent breaks apps expecting "Firefox" in the UA [f=myk, r=felipe, a=desktop-only]

Use the compatibility mode to include Firefox/<version> with WebappRuntime/<version>.

--HG--
extra : rebase_source : 3e8a5bbeb50ef3cca68c2a8bc618ded968449039

webapprt/prefs.js

@@ -3,3 +3,4 @@
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 pref("browser.chromeURL", "chrome://webapprt/content/webapp.xul");
+pref("general.useragent.compatMode.firefox", true);