Delete unnecessary construction of WebSocketFrame in NewWebSocketChannelImpl

After changes by inspector team that removed dependency from inspector
to WebSocket, the construction of WebSocketFrame there is meaningless.
Remove them.

BUG=none

Review URL: https://codereview.chromium.org/279783002

git-svn-id: svn://svn.chromium.org/blink/trunk@173750 bbb929c8-8fbe-4397-9dbb-9b2b20218538