Bug 1343442 - Re-enable browser_decoderDoctor.js on Mac - r=Gijs

Thanks to the previous patch, these tests can now be run on Mac, though they
don't do anything useful there just yet.

MozReview-Commit-ID: 3HyN7ms1EPl

--HG--
extra : rebase_source : c9487790d9c424dd8d21cfb6af927fd4121a15fa

browser/base/content/test/general/browser.ini

@@ -352,7 +352,6 @@ skip-if = toolkit == "gtk2" || toolkit == "gtk3" # disabled on Linux due to bug
 skip-if = !datareporting
 # DO NOT ADD MORE TESTS HERE. USE A TOPICAL DIRECTORY INSTEAD.
 [browser_decoderDoctor.js]
-skip-if = os == "mac" # decoder doctor isn't implemented on osx
 # DO NOT ADD MORE TESTS HERE. USE A TOPICAL DIRECTORY INSTEAD.
 [browser_discovery.js]
 # DO NOT ADD MORE TESTS HERE. USE A TOPICAL DIRECTORY INSTEAD.