MD History: Replace app-route with a custom router

chrome/browser/resources/md_history/router.js

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+Polymer({
+  is: 'history-router',
+
+  properties: {
+    selectedPage: {
+      type: String,
+      observer: 'serializePath_',
+      notify: true,
+    },
+
+    queryState: {
+      type: Object,
+      notify: true
+    },
+
+    path_: {
+      type: String,
+      observer: 'pathChanged_'
+    },
+
+    queryParams_: Object,
+  },
+
+  observers: [
+    'queryParamsChanged_(queryParams_.*)',
+    'searchTermChanged_(queryState.searchTerm)',
+  ],
+
+  /** @override */
+  attached: function() {
+    // Redirect legacy search URLs to URLs compatible with material history.
+    if (window.location.hash) {
+      window.location.href = window.location.href.split('#')[0] + '?' +
+          window.location.hash.substr(1);
+    }
+  },
+
+  /** @private */
+  serializePath_: function() {
+    var page = this.selectedPage == 'history' ? '' : this.selectedPage;
+    this.path_ = '/' + page;
+  },
+
+  /** @private */
+  pathChanged_: function() {
+    var sections = this.path_.substr(1).split('/');
+    this.selectedPage = sections[0] || 'history';
+  },
+
+  /** @private */
+  queryParamsChanged_: function() {
+    this.set('queryState.searchTerm', this.queryParams_.q || '');
+  },
+
+  /** @private */
+  searchTermChanged_: function() {
+    this.set('queryParams_.q', this.queryState.searchTerm || null);
+  },
+});