FileUpload.js: add the name of the file <input> to the post parameters.

javascript/src/FileUpload.js

@@ -66,6 +66,7 @@ var QfqNS = QfqNS || {};
         });
 
         data.append('s', this.sip);
+        data.append('name', fileInputName);
 
         return data;
     };