class Async::HTTP::Protocol::HTTP2::Response

def receive_headers(stream, headers, end_stream)

This should be invoked from the background reader, and notifies the task waiting for the headers that we are done. 
def receive_headers(stream, headers, end_stream)
	headers.each do |key, value|
		if key == STATUS
			@status = Integer(value)
		elsif key == CONTENT_LENGTH
			@length = Integer(value)
		elsif key == PROTOCOL
			@protocol = value
		else
			@headers[key] = value
		end
	end
	
	unless end_stream
		@body = @input = Body::Writable.new(@length)
	end
	
	notify!
end