Remove a dead test for non-final control frames.

WebSocketBasicStream cannot parse non-final control frames, therefore
there is no point in WebSocketChannel testing for them.

Also remove a test of the test, and change two other tests to use
control frames with invalid opcodes rather than invalid FIN bits.

BUG=347446
TEST=net_unittests, http/tests/websocket layout tests

Review URL: https://codereview.chromium.org/182543005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255040 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255040