Moves handling of thank you dialog.

Moves handling of thank you dialog out of the Promise that handles the feedback and just before we redirect to welcome page.

conference.js

@@ -202,8 +202,20 @@ function muteLocalVideo (muted) {
 
 /**
  * Check if the welcome page is enabled and redirects to it.
+ * If requested show a thank you dialog before that.
+ * @param {boolean} showThankYou whether we should show a thank you dialog
  */
-function maybeRedirectToWelcomePage() {
+function maybeRedirectToWelcomePage(showThankYou) {
+
+    if (showThankYou) {
+        APP.UI.messageHandler.openMessageDialog(
+            null, null, null,
+            APP.translation.translateString(
+                "dialog.thankYou", {appName:interfaceConfig.APP_NAME}
+            )
+        );
+    }
+
     if (!config.enableWelcomePage) {
         return;
     }

modules/UI/UI.js

@@ -1130,14 +1130,9 @@ UI.requestFeedback = function () {
                 }
             } else {
                 // If the feedback functionality isn't enabled we show a thank
-                // you dialog.
-                messageHandler.openMessageDialog(
-                    null, null, null,
-                    APP.translation.translateString(
-                        "dialog.thankYou", {appName:interfaceConfig.APP_NAME}
-                    )
-                );
-                resolve();
+                // you dialog. Signaling it (true), so the caller
+                // of requestFeedback can act on it
+                resolve(true);
             }
         });
 };