warn(SyntheticEvent): Update tests to check for warning when accessin…

…g properties on a destructored syntheticEvent

src/renderers/dom/client/syntheticEvents/__tests__/SyntheticEvent-test.js

@@ -81,6 +81,20 @@ describe('SyntheticEvent', function() {
     expect(syntheticEvent.target).toBe(null);
   });
 
+  it('should warn when accessing properties of a destructored synthetic event', function() {
+    var target = document.createElement('div');
+    var syntheticEvent = createEvent({srcElement: target});
+    syntheticEvent.destructor();
+    expect(syntheticEvent.type).toBe(null);
+    expect(console.error.calls.length).toBe(1);
+    expect(console.error.argsForCall[0][0]).toBe(
+      'Warning: This synthetic event is reused for performance reasons. If ' +
+      'you\'re seeing this, you\'re accessing a propertie on a ' +
+      'released/nullified synthetic event. This is set to null. See ' +
+      'https://fb.me/react-event-pooling for more information.'
+    );
+  });
+
   it('should warn if the synthetic event has been released when calling `preventDefault`', function() {
     spyOn(console, 'error');
     var syntheticEvent = createEvent({});