CONSOLE MESSAGE: line 22: ArrayBuffer is deprecated in XMLHttpRequest.send(). Use ArrayBufferView instead.
CONSOLE MESSAGE: line 22: ArrayBuffer is deprecated in XMLHttpRequest.send(). Use ArrayBufferView instead.
CONSOLE MESSAGE: line 22: ArrayBuffer is deprecated in XMLHttpRequest.send(). Use ArrayBufferView instead.

PASS setRequestHeader("") sends a blank string 
PASS setRequestHeader(" ") sends the string " " 
PASS setRequestHeader(null) sends the string "null" 
PASS setRequestHeader(undefined) sends the string "undefined" 
PASS String request has correct default Content-Type of "text/plain;charset=UTF-8" 
PASS String request keeps setRequestHeader() Content-Type, with charset adjusted to UTF-8 
PASS XML Document request respects setRequestHeader("") 
PASS XML Document request has correct default Content-Type of "application/xml;charset=UTF-8" 
PASS XML Document request keeps setRequestHeader() Content-Type, with charset adjusted to UTF-8 
PASS HTML Document request respects setRequestHeader("") 
PASS HTML Document request has correct default Content-Type of "text/html;charset=UTF-8" 
PASS HTML Document request keeps setRequestHeader() Content-Type, with charset adjusted to UTF-8 
PASS Blob request respects setRequestHeader("") to be specified 
FAIL Blob request with unset type sends no Content-Type without setRequestHeader() call assert_equals: expected "" but got "Content-Type: \n"
PASS Blob request with unset type keeps setRequestHeader() Content-Type and charset 
PASS Blob request with set type respects setRequestHeader("") to be specified 
PASS Blob request with set type uses that it for Content-Type unless setRequestHeader() 
PASS Blob request with set type keeps setRequestHeader() Content-Type and charset 
PASS ArrayBuffer request respects setRequestHeader("") 
PASS ArrayBuffer request sends no Content-Type without setRequestHeader() call 
PASS ArrayBuffer request keeps setRequestHeader() Content-Type and charset 
PASS ArrayBufferView request respects setRequestHeader("") 
PASS ArrayBufferView request sends no Content-Type without setRequestHeader() call 
PASS ArrayBufferView request keeps setRequestHeader() Content-Type and charset 
PASS FormData request respects setRequestHeader("") 
PASS FormData request has correct default Content-Type of "multipart/form-data; boundary=_" 
PASS FormData request keeps setRequestHeader() Content-Type and charset 
PASS URLSearchParams respects setRequestHeader("") 
FAIL URLSearchParams request has correct default Content-Type of "application/x-www-form-urlencoded;charset=UTF-8" assert_equals: expected "Content-Type: application/x-www-form-urlencoded;charset=UTF-8\n" but got "Content-Type: text/plain;charset=UTF-8\n"
PASS URLSearchParams request keeps setRequestHeader() Content-Type, with charset adjusted to UTF-8 
PASS ReadableStream request respects setRequestHeader("") 
FAIL ReadableStream request with under type sends no Content-Type without setRequestHeader() call assert_equals: expected "" but got "Content-Type: text/plain;charset=UTF-8\n"
FAIL ReadableStream request keeps setRequestHeader() Content-Type and charset assert_equals: expected "Content-Type: application/xml;charset=ASCII\n" but got "Content-Type: application/xml;charset=UTF-8\n"