[WebSocket] Fix a crash caused by a pending empty frame.

This CL fixes the process that sends pending frames when a WebSocketChannel
receives quota from the renderer process. The IOBuffer data of a frame can
be null, but the implementation didn't take account of that.

BUG=364788
[email protected]

Review URL: https://codereview.chromium.org/258833005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@266513 0039d316-1c4b-4281-b951-d872f2087c98
2 files changed