Fix preconnect crash on synchronous socket error.

GetAdditionalErrorState() was being called, which stores the error state into the ClientSocketHandle.  When we preconnect, we never have a ClientSocketHandle, so don't bother tryiing to store the error state nor get the error socket.

BUG=69214
TEST=net_unittests

Review URL: http://codereview.chromium.org/6293005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71481 0039d316-1c4b-4281-b951-d872f2087c98