feat (external-api) Add command for setting tile view mode

modules/API/API.js

 import { toggleLobbyMode } from '../../react/features/lobby/actions.web';
 import { RECORDING_TYPES } from '../../react/features/recording/constants';
 import { getActiveSession } from '../../react/features/recording/functions';
-import { toggleTileView } from '../../react/features/video-layout';
+import { toggleTileView, setTileView } from '../../react/features/video-layout';
 import { muteAllParticipants } from '../../react/features/video-menu/actions';
 import { setVideoQuality } from '../../react/features/video-quality';
 import { getJitsiMeetTransport } from '../transport';
 
             APP.store.dispatch(toggleTileView());
         },
+        'set-tile-view': enabled => {
+            APP.store.dispatch(setTileView(enabled));
+        },
         'video-hangup': (showFeedbackDialog = true) => {
             sendAnalytics(createApiEvent('video.hangup'));
             APP.conference.hangup(showFeedbackDialog);

modules/API/external/external_api.js

     sendEndpointTextMessage: 'send-endpoint-text-message',
     sendTones: 'send-tones',
     setLargeVideoParticipant: 'set-large-video-participant',
+    setTileView: 'set-tile-view',
     setVideoQuality: 'set-video-quality',
     startRecording: 'start-recording',
     stopRecording: 'stop-recording',