In bug 1393150, the two WebExt tests at: devtools/server/tests/mochitest/test_webextension-addon-debugging* were marked as "skip-if = !e10s" as way to say "only run with e10s on". Unfortunately, these are chrome tests which always run with e10s = false (it's up to the test to invoke remote behavior if it wants to), so this means they have been effectively disabled since. However, this doesn't seem to stop test-verify from running them anyway, and they are now broken by various other code changes. For now, I will be marking them disabled in bug 1172897 to avoid test-verify errors, but someone should decide the fate of these tests.

Pushed by luca.greco@alcacoop.it: https://hg.mozilla.org/integration/autoland/rev/380804a8d81c Replace disabled addon debugging mochitest-chrome test with a new devtools xpcshell test. r=jdescottes