public function removeUserMetaKey( $user_meta_key ) {
		$filter = function( $meta_key ) use ( $user_meta_key ) {
			return $meta_key !== $user_meta_key;
		};
		$this->avatar_user_meta_keys = array_filter( $this->avatar_user_meta_keys, $filter );
	}
public function removeUserMetaKey( $user_meta_key ) {
		$filter = function( $meta_key ) use ( $user_meta_key ) {
			return $meta_key !== $user_meta_key;
		};
		$this->avatar_user_meta_keys = array_filter( $this->avatar_user_meta_keys, $filter );
	}
public function removeUserMetaKey ( $ user_meta_key ) { $ filter = function ( $ meta_key ) use ( $ user_meta_key ) { return $ meta_key !== $ user_meta_key ; } ; $ this -> avatar_user_meta_keys = array_filter ( $ this -> avatar_user_meta_keys , $ filter ) ; }
Remove a previously added meta key

@param  string $user_meta_key
@return void
Remove a previously added meta key