Merge branch '2.x' into 2.1
Merge branch '2.x' into 2.1
exceedable simultaneous uploads and total file size

In XHR file upload, upload exceeding the number of the maximum
simultaneous upload files of a server setup and the maximum upload file
size (sum total value of two or more files) was enabled.
Merge branch '2.1' into 2.1_n