avatars: ensure no remote avatar is loaded when disableThirdPartyRequests is set

react/features/base/participants/middleware.js

     // to the new avatar and emit out change events if necessary.
     const result = next(action);
 
-    if (avatarURL || email || id || name) {
+    const { disableThirdPartyRequests } = getState()['features/base/config'];
+
+    if (!disableThirdPartyRequests && (avatarURL || email || id || name)) {
         const participantId = !id && local ? getLocalParticipant(getState()).id : id;
         const updatedParticipant = getParticipantById(getState(), participantId);
 

react/features/base/participants/preloadImage.web.js

 
 import { isIconUrl } from './functions';
 
-declare var config: Object;
-
 /**
  * Tries to preload an image.
  *
         return Promise.resolve(src);
     }
 
-    if (typeof config === 'object' && config.disableThirdPartyRequests) {
-        return Promise.reject();
-    }
-
     return new Promise((resolve, reject) => {
         const image = document.createElement('img');