Fix url_unittests URLCanonTest.DoAppendUTF8Invalid failures with dcheck_always_on

Just make the test disabled as if in Debug mode.

BUG=383311
R=brettw@chromium.org

Review URL: https://codereview.chromium.org/331693005

git-svn-id: https://src.chromium.org/chrome/trunk/src/url@277600 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Replace some hard coded schemes with the constants in /url/url_constants.h.

BUG=none
TEST=compile

Review URL: https://codereview.chromium.org/335353002

git-svn-id: https://src.chromium.org/chrome/trunk/src/url@277979 4ff67af0-8c30-449e-8e8b-ad334ec8d88c