cloudweb-5925: beautify code

Author: Octane

lib/FileAPI.core.js

@@ -1518,7 +1518,7 @@
 _one(reader, _readerEvents, function (evt){
 var isFile = evt.type != 'error';
 if( isFile ){
-if ( reader.readyState == void 0 || reader.readyState === 1 /*LOADING*/ ) {
+if ( reader.readyState == null || reader.readyState === reader.LOADING ) {
 reader.abort();
 }
 callback(isFile);