Implement create attribute API functions for BTLE.

device/bluetooth/bluetooth_adapter_android.cc

Index: device/bluetooth/bluetooth_adapter_android.cc
diff --git a/device/bluetooth/bluetooth_adapter_android.cc b/device/bluetooth/bluetooth_adapter_android.cc
index 7e749984d1dcdcb305477c50136f4167c9dd745c..ddbdf337dd94e5a3891f365d7096603d1e392e64 100644
--- a/device/bluetooth/bluetooth_adapter_android.cc
+++ b/device/bluetooth/bluetooth_adapter_android.cc
@@ -141,6 +141,11 @@ void BluetoothAdapterAndroid::RegisterAdvertisement(
   error_callback.Run(BluetoothAdvertisement::ERROR_UNSUPPORTED_PLATFORM);
 }
 
+BluetoothLocalGattService* BluetoothAdapterAndroid::GetGattService(
+    const std::string& identifier) const {
+  return nullptr;
+}
+
 void BluetoothAdapterAndroid::OnAdapterStateChanged(
     JNIEnv* env,
     const JavaParamRef<jobject>& caller,