Disable Polymer's Synthetic Click Canceling

This config enabled is really for legacy mobile browser support,
this is no longer needed, so lets disable it.

This also fixes file uploads in mobiles.

See Polymer/polymer#5533

Change-Id: I2144b848a892e6b908dcc153fed42b9223c06272

polygerrit-ui/app/elements/gr-app.js

@@ -23,6 +23,16 @@
 import './gr-app-init.js';
 import './font-roboto-local-loader.js';
 import '../scripts/bundled-polymer.js';
+
+/**
+ * setCancelSyntheticClickEvents is set to true by
+ * default which will cancel synthetic click events
+ * on older touch device.
+ * See https://github.com/Polymer/polymer/issues/5289
+ */
+import {setCancelSyntheticClickEvents} from '@polymer/polymer/lib/utils/settings.js';
+setCancelSyntheticClickEvents(false);
+
 import 'polymer-resin/standalone/polymer-resin.js';
 import {initGlobalVariables} from './gr-app-global-var-init.js';
 // Initialize global variables before any other imports