Add JS code for websocket throttling browser test.
Add JS code for websocket throttling browser test.

Bug: 423246
Change-Id: I27dcc6fbee60a9827299fdc84185c4590ec48107
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/3245371
Commit-Queue: Danil Somsikov <f16a5ee11618cab93684e694f9aa762d34f02920@chromium.org>
Auto-Submit: Danil Somsikov <f16a5ee11618cab93684e694f9aa762d34f02920@chromium.org>
Reviewed-by: Wolfgang Beyer <573aa99bb19da47d816981118f95c945310dd3f4@chromium.org>
Reviewed-by: Simon Zünd <38944668e9e2ca98ccd0275b53370f90fa55c113@chromium.org>

ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend,ChromeDevTools/devtools-frontend