Previously, an unparseable status line would give an "Unexpected
response code: 200" console error, which didn't make much sense.

This is because HttpStreamParser synthesises an "HTTP/0.9 200 OK" status line if it doesn't see the string "HTTP" within the first 8 bytes of the response.

Use a specific "Invalid status line" error message in this case instead.

BUG=345568

Review URL: https://codereview.chromium.org/173523004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@252536 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 252536