2 Bug 22475: REGRESSION: Async XMLHttpRequest never finishes on nonexistent files anymore
4 In both cases, readyState 4 should be reached, and error handler should be invoked.
6 Doing an XHR to a nonexistent file.
7 ReadyState handler: readyState = 1
8 ReadyState handler: readyState = 4
9 Error handler: readyState = 4
11 Doing an XHR to a directory.
12 ReadyState handler: readyState = 1
13 ReadyState handler: readyState = 4