feat(visitors): Adds option to disable self-demote button.

Fixes #14539

config.js

@@ -121,6 +121,9 @@ var config = {
     // Disables polls feature.
     // disablePolls: false,
 
+    // Disables demote button from self-view
+    // disableSelfDemote: false,
+
     // Disables self-view tile. (hides it from tile view and from filmstrip)
     // disableSelfView: false,
 

react/features/base/config/configType.ts

@@ -287,6 +287,7 @@ export interface IConfig {
     disableRemoveRaisedHandOnFocus?: boolean;
     disableResponsiveTiles?: boolean;
     disableRtx?: boolean;
+    disableSelfDemote?: boolean;
     disableSelfView?: boolean;
     disableSelfViewSettings?: boolean;
     disableShortcuts?: boolean;

react/features/base/config/configWhitelist.ts

@@ -116,6 +116,7 @@ export default [
     'disableRemoteMute',
     'disableResponsiveTiles',
     'disableRtx',
+    'disableSelfDemote',
     'disableSelfView',
     'disableSelfViewSettings',
     'disableShortcuts',

react/features/video-menu/components/native/LocalVideoMenu.tsx

@@ -141,12 +141,13 @@ class LocalVideoMenu extends PureComponent<IProps> {
  * @returns {IProps}
  */
 function _mapStateToProps(state: IReduxState) {
+    const { disableSelfDemote } = state['features/base/config'];
     const participant = getLocalParticipant(state);
 
     return {
         _participant: participant,
         _participantDisplayName: getParticipantDisplayName(state, participant?.id ?? ''),
-        _showDemote: getParticipantCount(state) > 1
+        _showDemote: !disableSelfDemote && getParticipantCount(state) > 1
     };
 }
 

react/features/video-menu/components/web/LocalVideoMenuTriggerButton.tsx

@@ -268,7 +268,7 @@ const LocalVideoMenuTriggerButton = ({
 function _mapStateToProps(state: IReduxState, ownProps: Partial<IProps>) {
     const { thumbnailType } = ownProps;
     const localParticipant = getLocalParticipant(state);
-    const { disableLocalVideoFlip, disableSelfViewSettings } = state['features/base/config'];
+    const { disableLocalVideoFlip, disableSelfDemote, disableSelfViewSettings } = state['features/base/config'];
     const videoTrack = getLocalVideoTrack(state['features/base/tracks']);
     const { overflowDrawer } = state['features/toolbox'];
     const { showConnectionInfo } = state['features/base/connection'];
@@ -292,7 +292,7 @@ function _mapStateToProps(state: IReduxState, ownProps: Partial<IProps>) {
 
     return {
         _menuPosition,
-        _showDemote: getParticipantCount(state) > 1,
+        _showDemote: !disableSelfDemote && getParticipantCount(state) > 1,
         _showLocalVideoFlipButton: !disableLocalVideoFlip && videoTrack?.videoType !== 'desktop',
         _showHideSelfViewButton: showHideSelfViewButton,
         _overflowDrawer: overflowDrawer,