[DevTools] Encode binary websocket messages as base64

Bug: 914963
Change-Id: I9c468b9cbcff5cc5fe90385e14a749532238c3d4
Reviewed-on: https://chromium-review.googlesource.com/c/1377182
Reviewed-by: Andrey Kosyakov <caseq@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Joey Arhar <jarhar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#616793}
4 files changed