[patch][cla] dojo/_base/xhr does not respect contentType in __XhrArgs

[kbenjamin]

The contentType arg is not implemented the same way in dojo/request/xhr and no accommodation was made for that in dojo/_base/xhr which now calls dojo/request/xhr.

The result is that the Content-Type header is set to defaults, not the specified value.

Impacted modules: dojo/rpc/JsonService, various dojox/*, probably lots of stuff in the wild.

The fix is simple. In dojo/_base/xhr::dojo.xhr(): Insert at line 611 (just after the block dealing with args.headers):

		if(typeof args.contentType !== 'undefined'){
			if(typeof options.headers == 'undefined'){
				options.headers = {};
			}
			options.headers['Content-Type'] = args.contentType;
		}

A patched version of dojo/_base/xhr is attached.

[kbenjamin]

dojo/_base/xhr - Fix to support contentType

[kbenjamin]

In further research, I've found that there are no tests that directly call xhr() and, therefore, none that test setting contentType, which is one reason this regression was not discovered.

I realize that with dojo/_base/xhr deprecated that such a test might be a waste of time but considering the potential impact of this regression, I'm not so sure.

The tests for dojo/rpc also do not surface the regression as they do not check Content-Type headers in resources/test_JsonRPCMediator.php.

I'll attempt to create a diff file to upload per Kitson's suggestion.

[kbenjamin]

diff from github master

[Bryan Forbes]

In [29261]:

Fix for contentType property to dojo.xhr*. refs #15591 !strict