Don't run this spec on platforms where the method is unavailable.

spec/api-app-spec.js

@@ -7,6 +7,7 @@ const remote = require('electron').remote
 
 const app = remote.require('electron').app
 const BrowserWindow = remote.require('electron').BrowserWindow
+const isCI = remote.getGlobal('isCi')
 
 describe('electron module', function () {
   it('allows old style require by default', function () {
@@ -90,6 +91,10 @@ describe('app module', function () {
   })
 
   describe('app.setUserActivity(type, userInfo)', function () {
+    if (isCI && process.platform !== 'darwin') {
+      return
+    }
+
     it('sets the current activity', function () {
       app.setUserActivity('com.electron.testActivity', {testData: '123'});
       assert.equal(app.getCurrentActivityType(), 'com.electron.testActivity');