Add a clarification comment to WebSocketHandshake::m_response

Explains what kind of change can be made from the original data received from
the server.

BUG=none

Review URL: https://codereview.chromium.org/31753002

git-svn-id: svn://svn.chromium.org/blink/trunk@160176 bbb929c8-8fbe-4397-9dbb-9b2b20218538
scroll: Tell the platform layer whether it can be scrolled by the user.

BUG=175502

Review URL: https://codereview.chromium.org/33413002

git-svn-id: svn://svn.chromium.org/blink/trunk@160177 bbb929c8-8fbe-4397-9dbb-9b2b20218538