[WebAudio DevTools] Add new graph events to browser_protocol.pdl

This is a follow-up CL of:
https://chromium-review.googlesource.com/c/chromium/src/+/1726957

This CL introduces the actual event hooks between the WebAudio module
and the devtool frontend.

This CL completes the backend for the graph visualizer. On top of
this change, the graph visualizer is ready for the implementation.

Bug: 970898
Change-Id: I76fae9d19d501158fac3c13cb6226d72fccb798c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1728265
Reviewed-by: Andrey Kosyakov <[email protected]>
Reviewed-by: Raymond Toy <[email protected]>
Reviewed-by: Erik Luo <[email protected]>
Commit-Queue: Hongchan Choi <[email protected]>
Cr-Original-Commit-Position: refs/heads/master@{#685048}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 87be32736e44c5fa9ca6b34a31cdff17e0e2abec
diff --git a/front_end/web_audio/WebAudioView.js b/front_end/web_audio/WebAudioView.js
index 9944ea7..58f5a71 100644
--- a/front_end/web_audio/WebAudioView.js
+++ b/front_end/web_audio/WebAudioView.js
@@ -151,7 +151,7 @@
   }
 
   /**
-   * @param {!Protocol.WebAudio.ContextId} contextId
+   * @param {!Protocol.WebAudio.GraphObjectId} contextId
    * @param {!Protocol.WebAudio.ContextRealtimeData} contextRealtimeData
    */
   _updateSummaryBar(contextId, contextRealtimeData) {