bluetooth: android: Implement Characteristic GetIdentifier, fix Service IDs too.

device/bluetooth/bluetooth_remote_gatt_service_android.h

 // 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.
 
 #ifndef DEVICE_BLUETOOTH_BLUETOOTH_REMOTE_GATT_SERVICE_ANDROID_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_REMOTE_GATT_SERVICE_ANDROID_H_
 
 #include <map>
 #include <string>
 #include <vector>
@@ skipping 22 matching lines @@
   // The ChromeBluetoothRemoteGattService instance will hold a Java reference
   // to |bluetooth_remote_gatt_service_wrapper|.
   //
   // TODO(scheib): Return a scoped_ptr<>, but then device will need to handle
   // this correctly. http://crbug.com/506416
   static BluetoothRemoteGattServiceAndroid* Create(
       BluetoothAdapterAndroid* adapter,
       BluetoothDeviceAndroid* device,
       jobject bluetooth_remote_gatt_service_wrapper,  // Java Type:
       // BluetoothRemoteGattServiceWrapper
-      std::string instanceId);
+      const std::string& instanceId);
 
   // Register C++ methods exposed to Java using JNI.
   static bool RegisterJNI(JNIEnv* env);
 
   // Returns the associated ChromeBluetoothRemoteGattService Java object.
   base::android::ScopedJavaLocalRef<jobject> GetJavaObject();
 
   // device::BluetoothGattService overrides.
   std::string GetIdentifier() const override;
   device::BluetoothUUID GetUUID() const override;
@@ skipping 21 matching lines @@
       jobject caller,
       const jstring& instanceId,
       jobject /* BluetoothGattCharacteristicWrapper */
       bluetooth_gatt_characteristic_wrapper);
 
  private:
   friend class BluetoothDeviceAndroid;
 
   BluetoothRemoteGattServiceAndroid(BluetoothAdapterAndroid* adapter,
                                     BluetoothDeviceAndroid* device,
-                                    std::string instanceId);
+                                    const std::string& instanceId);
   ~BluetoothRemoteGattServiceAndroid() override;
 
   // Populates |characteristics_| from Java objects if necessary.
   void EnsureCharacteristicsCreated() const;
 
   // Java object org.chromium.device.bluetooth.ChromeBluetoothRemoteGattService.
   base::android::ScopedJavaGlobalRef<jobject> j_service_;
 
   // The adapter associated with this service. It's ok to store a raw pointer
   // here since |adapter_| indirectly owns this instance.
   BluetoothAdapterAndroid* adapter_;
 
   // The device this GATT service belongs to. It's ok to store a raw pointer
   // here since |device_| owns this instance.
   BluetoothDeviceAndroid* device_;
 
-  // Instance ID, cached from Android object.
+  // Adapter unique instance ID.
   std::string instanceId_;
 
   // Map of characteristics, keyed by characteristic identifier.
   base::ScopedPtrHashMap<std::string,
                          scoped_ptr<BluetoothRemoteGattCharacteristicAndroid>>
       characteristics_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothRemoteGattServiceAndroid);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_BLUETOOTH_BLUETOOTH_REMOTE_GATT_SERVICE_ANDROID_H_