Bug 1281213 - Fix passing of app_args to gecko instance in Marionette client; r=automatedtester

MozReview-Commit-ID: EuLGjT2Vlfn

--HG--
extra : rebase_source : 133f440cc047afe6e2f09e8f7d6e272be0119990

testing/marionette/client/marionette_driver/marionette.py

@@ -591,6 +591,7 @@ class Marionette(object):
                     instance_class = geckoinstance.GeckoInstance
             self.instance = instance_class(host=self.host, port=self.port,
                                            bin=self.bin, profile=self.profile,
+                                           app_args=app_args,
                                            symbols_path=symbols_path,
                                            gecko_log=gecko_log, prefs=prefs,
                                            addons=self.addons,