Bug 1219842 followup, redisable dom/plugins/test/mochitest/test_crashing.html on debug e10s until its assertion problem is dealt with

dom/plugins/test/mochitest/mochitest.ini

@@ -53,7 +53,7 @@ skip-if = (toolkit != "gtk2") && (toolkit != "gtk3")
 [test_crash_nested_loop.html]
 skip-if = (toolkit != "gtk2") && (toolkit != "gtk3")
 [test_crashing.html]
-skip-if = !crashreporter
+skip-if = !crashreporter || (e10s && debug)
 [test_crashing2.html]
 skip-if = (!crashreporter) || true # Bug 566049
 [test_CrashService_crash.html]