Refactor Websocket test classes.

Factor out FakeWebSocketBasicHandshakeStream and
FakeWebSocketHandshakeStream into websocket_test_util.

Bug: 801564
Change-Id: I093667de806f7d4879144bac447e45663219c5a1
Reviewed-on: https://chromium-review.googlesource.com/891444
Commit-Queue: Bence Béky <bnc@chromium.org>
Reviewed-by: Adam Rice <ricea@chromium.org>
Cr-Commit-Position: refs/heads/master@{#532853}
4 files changed