Bug 1491484 - Skip less of browser_findbar.js on linux opt;r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D8390

--HG--
extra : moz-landing-system : lando

toolkit/content/tests/browser/browser.ini

@@ -98,7 +98,6 @@ uses-unsafe-cpows = true
 [browser_default_image_filename_redirect.js]
 [browser_f7_caret_browsing.js]
 [browser_findbar.js]
-skip-if = os == "linux" && !debug # Bug 1491484
 [browser_findbar_disabled_manual.js]
 [browser_isSynthetic.js]
 [browser_keyevents_during_autoscrolling.js]

toolkit/content/tests/browser/browser_findbar.js

@@ -168,6 +168,11 @@ add_task(async function e10sLostKeys() {
     return;
   }
 
+  if (AppConstants.platform == "linux" && !AppConstants.DEBUG) {
+    info("Skipping this test because of linux opt (Bug 1491484).");
+    return;
+  }
+
   let tab = await BrowserTestUtils.openNewForegroundTab(gBrowser, TEST_PAGE_URI);
 
   ok(!gFindBarInitialized, "findbar isn't initialized yet");