NOT FOR SUBMIT: use counters for jdm@

third_party/WebKit/Source/modules/serviceworkers/Client.idl

 // Copyright 2014 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://w3c.github.io/ServiceWorker/#service-worker-client-interface
 [
     Exposed=ServiceWorker,
     ImplementedAs=ServiceWorkerClient,
 ] interface Client {
-    readonly attribute USVString url;
-    readonly attribute ContextFrameType frameType;
-    readonly attribute DOMString id;
-    [PostMessage, RaisesException, CallWith=ExecutionContext] void postMessage(SerializedScriptValue message, optional sequence<Transferable> transfer);
+    [Measure] readonly attribute USVString url;
+    [Measure] readonly attribute ContextFrameType frameType;
+    [Measure] readonly attribute DOMString id;
+  [Measure, PostMessage, RaisesException, CallWith=ExecutionContext] void postMessage(SerializedScriptValue message, optional sequence<Transferable> transfer);
 };