DevTools: Add a test for disabling breakpoints.

The test is added disabled since this functionality is currently broken

BUG=432493
R=pfeldman, yurys, sergeyv

Review URL: https://codereview.chromium.org/724053003

git-svn-id: svn://svn.chromium.org/blink/trunk@185304 bbb929c8-8fbe-4397-9dbb-9b2b20218538