Call preventDefault in all on-tap events that show a dialog.

chrome/browser/resources/settings/bluetooth_page/bluetooth_page.js

 // Copyright 2015 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.
 
 /**
  * @fileoverview
  * 'settings-bluetooth-page' is the settings page for managing bluetooth
  *  properties and devices.
  *
  * Example:
@@ skipping 356 matching lines @@
     }
     if (e.pairing == chrome.bluetoothPrivate.PairingEventType.KEYS_ENTERED &&
         e.passkey === undefined && this.pairingEvent_) {
       // 'keysEntered' event might not include the updated passkey so preserve
       // the current one.
       e.passkey = this.pairingEvent_.passkey;
     }
     this.pairingEvent_ = e;
   },
 
-  /** @private */
-  onAddDeviceTap_: function() {
+  /**
+   * @param {!Event} e
+   * @private
+   */
+  onAddDeviceTap_: function(e) {
+    e.preventDefault();
     this.openDialog_('addDevice');
   },
 
   /**
    * @param {!{detail: {action: string, device: !chrome.bluetooth.Device}}} e
    * @private
    */
   onDeviceEvent_: function(e) {
     var action = e.detail.action;
     var device = e.detail.device;
@@ skipping 177 matching lines @@
   },
 
   /** @private */
   onDialogClosed_: function() {
     this.stopDiscovery_();
     this.dialogId_ = '';
     this.pairingDevice_ = null;
     this.pairingEvent_ = null;
   },
 });