Bug 1457545 - Part 3 - Re-enable crash tests for Mac opt builds r=whimboo

MozReview-Commit-ID: 9moWdhFSNkH

--HG--
extra : rebase_source : dcc443c33b252f5baf433b3a0aac60d3647fbdea

testing/marionette/harness/marionette_harness/tests/unit/unit-tests.ini

@@ -124,5 +124,5 @@ skip-if = appname == 'fennec' # Bug 1330598
 
 [test_select.py]
 [test_crash.py]
-skip-if = asan || manage_instance == false || appname == 'fennec' || (os == 'mac' && !debug) # Bug 1298921, bug 1376773
+skip-if = asan || manage_instance == false || appname == 'fennec' # Bug 1298921
 [test_localization.py]