Bug 1303062 - Turn on first party isolation tests. r=baku

--HG--
extra : rebase_source : 1072dc1e8c015b41d67992af2c7aa1984aaea958

browser/components/originattributes/test/browser/head.js

@@ -176,7 +176,7 @@ this.IsolationTestTools = {
     add_task(function* addTaskForIsolationTests() {
       let testSettings = [
         { mode: TEST_MODE_FIRSTPARTY,
-          skip: true,
+          skip: false,
           prefs: [["privacy.firstparty.isolate", true]]
         },
         { mode: TEST_MODE_NO_ISOLATION,