Test that setRequestHeader throws a SYNTAX_ERR exception when called with an empty header name.
SUCCESS: got exception SyntaxError: Failed to execute 'setRequestHeader' on 'XMLHttpRequest': '' is not a valid HTTP header field name.
Test that setRequestHeader throws a SYNTAX_ERR exception when called with an empty header name.
SUCCESS: got exception SyntaxError: Failed to execute 'setRequestHeader' on 'XMLHttpRequest': '' is not a valid HTTP header field name.