Allow HttpServer response to include custom headers.

This is done by introducing a simple HttpServerResponseInfo class, and
changing the root HttpServer::Send to accept it instead of a status, data, and
mime type.
BUG=none

Review URL: https://chromiumcodereview.appspot.com/19637005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@213227 0039d316-1c4b-4281-b951-d872f2087c98
12 files changed