ref(notifications): convert Thank You message to a notification

conference.js

     setVideoAvailable,
     setVideoMuted
 } from './react/features/base/media';
+import { showNotification } from './react/features/notifications';
 import {
     dominantSpeakerChanged,
     getAvatarURLByParticipantId,
  *
  * @param {object} options used to decide which particular close page to show
  * or if close page is disabled, whether we should show the thankyou dialog
- * @param {boolean} options.thankYouDialogVisible - whether we should
+ * @param {boolean} options.showThankYou - whether we should
  * show thank you dialog
  * @param {boolean} options.feedbackSubmitted - whether feedback was submitted
  */
     }
 
     // else: show thankYou dialog only if there is no feedback
-    if (options.thankYouDialogVisible) {
-        APP.UI.messageHandler.openMessageDialog(
-            null, 'dialog.thankYou', { appName: interfaceConfig.APP_NAME });
+    if (options.showThankYou) {
+        APP.store.dispatch(showNotification({
+            titleArguments: { appName: interfaceConfig.APP_NAME },
+            titleKey: 'dialog.thankYou'
+        }));
     }
 
     // if Welcome page is enabled redirect to welcome page after 3 sec.

react/features/feedback/actions.js

 export function maybeOpenFeedbackDialog(conference: Object) {
     type R = {
         feedbackSubmitted: boolean,
-        thankYouDialogVisible: boolean
+        showThankYou: boolean
     };
 
     return (dispatch: Dispatch<*>, getState: Function): Promise<R> => {
 
             return Promise.resolve({
                 feedbackSubmitted: true,
-                thankYouDialogVisible: true
+                showThankYou: true
             });
         } else if (conference.isCallstatsEnabled()) {
             return new Promise(resolve => {
 
                     resolve({
                         feedbackSubmitted: submitted,
-                        thankYouDialogVisible: false
+                        showThankYou: false
                     });
                 }));
             });
         }
 
         // If the feedback functionality isn't enabled we show a "thank you"
-        // dialog. Signaling it (true), so the caller of requestFeedback can act
-        // on it.
+        // message. Signaling it (true), so the caller of requestFeedback can
+        // act on it.
         return Promise.resolve({
             feedbackSubmitted: false,
-            thankYouDialogVisible: true
+            showThankYou: true
         });
     };
 }