Merge "Guard double-showing of user credentials dialog" into nyc-dev

            final Bundle args = new Bundle();

            args.putParcelable(ARG_CREDENTIAL, item);

            final CredentialDialogFragment frag = new CredentialDialogFragment();

            if (target.getFragmentManager().findFragmentByTag(TAG) == null) {

                final DialogFragment frag = new CredentialDialogFragment();

                frag.setTargetFragment(target, /* requestCode */ -1);

                frag.setArguments(args);

                frag.show(target.getFragmentManager(), TAG);

            }

        }

        @Override

        public Dialog onCreateDialog(Bundle savedInstanceState) {