md-settings: Fix back navigation from /resetProfileSettings.

chrome/test/data/webui/polymer_browser_test_base.js

Index: chrome/test/data/webui/polymer_browser_test_base.js
diff --git a/chrome/test/data/webui/polymer_browser_test_base.js b/chrome/test/data/webui/polymer_browser_test_base.js
index ea1b659bd20acea58e321574394c39084e4cd107..b63110cd36f562c154c2028349724d90f5e5038f 100644
--- a/chrome/test/data/webui/polymer_browser_test_base.js
+++ b/chrome/test/data/webui/polymer_browser_test_base.js
@@ -206,3 +206,16 @@ PolymerTest.getLibraries = function(basePath) {
     return basePath + library;
   });
 };
+
+/*
+ * Waits for queued up tasks to finish before proceeding. Inspired by:
+ * https://github.com/Polymer/web-component-tester/blob/master/browser/environment/helpers.js#L97
+ */
+PolymerTest.flushTasks = function() {
+  Polymer.dom.flush();
+  // Promises have microtask timing, so we use setTimeout to explicity force a
+  // new task.
+  return new Promise(function(resolve, reject) {
+    window.setTimeout(resolve, 0);
+  });
+};