Move Bluetooth.Web.FunctionCall.Count UMA from browser to WebKit

third_party/WebKit/Source/modules/bluetooth/BluetoothRemoteGATTDescriptor.idl

 // 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.
 
 // https://webbluetoothcg.github.io/web-bluetooth/#bluetoothremotegattdescriptor
 
 // Implement BluetoothRemoteGATTDescriptor interface: https://crbug.com/660699
 
 [
     RuntimeEnabled=WebBluetooth,
 ] interface BluetoothRemoteGATTDescriptor  {
     [SameObject] readonly attribute BluetoothRemoteGATTCharacteristic characteristic;
     readonly attribute UUID uuid;
     readonly attribute DataView? value;
-    [CallWith=ScriptState] Promise<DataView> readValue();
-    [CallWith=ScriptState] Promise<void> writeValue(BufferSource value);
+    [CallWith=ScriptState, MeasureAs=WebBluetoothRemoteDescriptorReadValue] Promise<DataView> readValue();
+    [CallWith=ScriptState, MeasureAs=WebBluetoothRemoteDescriptorWriteValue] Promise<void> writeValue(BufferSource value);
 };