feat(line-ripple): typescript issues in tests

Author: gugu

test/unit/line-ripple/index.test.tsx

@@ -3,12 +3,14 @@ import * as td from 'testdouble';
 import {assert} from 'chai';
 import {shallow} from 'enzyme';
 import LineRipple from '../../../packages/line-ripple/index';
+import {MDCLineRippleFoundation} from '@material/line-ripple/foundation';
 import {MDCLineRippleAdapter} from '@material/line-ripple/adapter';
 import {coerceForTesting} from '../helpers/types';
 
 suite('LineRipple');
 
-function getAdapter(foundation: any): MDCLineRippleAdapter {
+function getAdapter(foundation: MDCLineRippleFoundation): MDCLineRippleAdapter {
+  // @ts-ignore adapter_ property is protected, we need to bypass this check for testing purposes
   return foundation.adapter_;
 }
 
@@ -109,11 +111,11 @@ test('#adapter.setStyle updates style', () => {
 test('onTransitionEnd calls the #foundation.handleTransitionEnd', () => {
   const wrapper = shallow<LineRipple>(<LineRipple />);
   wrapper.instance().foundation_.handleTransitionEnd = td.func<(env: TransitionEvent) => null>();
-  const event: React.TransitionEvent = {
+  const event: React.TransitionEvent = coerceForTesting<React.TransitionEvent>({
     nativeEvent: {
       test: '123',
     },
-  } as any;
+  });
   wrapper.simulate('transitionEnd', event);
   td.verify(wrapper.instance().foundation_.handleTransitionEnd(event.nativeEvent), {
     times: 1,