Removed the DATA_IMAGE_USER_DOT_PIC

Because viewUserPic is always false due to the removed Gravatar feature

dev/Common/Cache.js

@@ -22,15 +22,6 @@ export function clear() {
 	MESSAGE_FLAGS_CACHE = {};
 }
 
-/**
- * @param {string} email
- * @param {Function} callback
- * @returns {string}
- */
-export function getUserPic(email, callback) {
-	callback('', email.trim());
-}
-
 /**
  * @param {string} folderFullNameRaw
  * @param {string} uid