Merge pull request #15797 from Mugen87/dev23

ImageBitmapLoader: Fix usage of loading manager

src/loaders/ImageBitmapLoader.js

@@ -90,6 +90,8 @@ ImageBitmapLoader.prototype = {
 
 		} );
 
+		scope.manager.itemStart( url );
+
 	},
 
 	setCrossOrigin: function ( /* value */ ) {