cc: Defer first OutputSurface creation until client is ready

Remove the |first_output_surface| which was not used before
the client signals ready.
This allows the client to wait before creating a graphics context
until the gpu thread and client channel are set up.

BUG=270179,329739
R=danakj@chromium.org, jamesr@chromium.org, jochen@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=238458

Review URL: https://codereview.chromium.org/85693007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241897 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241897
Prefix string16 with base:: in ash/.

R=sky@chromium.org
BUG=329295

Review URL: https://codereview.chromium.org/118903002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241898 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241898