bluetooth: Add characteristic list to DeviceDetailsPage in internals page.

chrome/browser/resources/bluetooth_internals/device_details_page.js

 // Copyright 2017 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.
 
 /**
  * Javascript for DeviceDetailsPage which displays all of the details of a
  * device. The page is generated and managed dynamically in bluetooth_internals.
  * served from chrome://bluetooth-internals/.
  */
 
@@ skipping 65 matching lines @@
                 address: this.deviceInfo.address,
               },
           }));
         }.bind(this));
 
     this.connectBtn_ = this.pageDiv.querySelector('.disconnect');
     this.connectBtn_.addEventListener('click', function() {
       this.devicePtr !== null ? this.disconnect() : this.connect();
     }.bind(this));
 
+    this.serviceList.addEventListener(
+        'characteristicsrequested', function(event) {
+          if (!this.devicePtr) {
+            event.target.onCharacteristicsRequested([]);
+            return;
+          }
+
+          this.devicePtr.getCharacteristics(event.detail.serviceId).then(
+              function(response) {
+                event.target.onCharacteristicsRequested(
+                    response.characteristics);
+              }.bind(this));
+        }.bind(this));
+
     this.redraw();
   }
 
   DeviceDetailsPage.prototype = {
     __proto__: Page.prototype,
 
     /** Creates a connection to the Bluetooth device. */
     connect: function() {
       if (this.status_ !== device_collection.ConnectionStatus.DISCONNECTED)
         return;
@@ skipping 128 matching lines @@
           status: status,
         }
       }));
     },
   };
 
   return {
     DeviceDetailsPage: DeviceDetailsPage,
   };
 });