fix(send-type): apply custom headers when passed a stream (#198)

* Fixes #197: apply custom headers when passed a stream

* Use setHeader instead of writeHead to fix Chrome issue

* Use for…in loop as suggested by Luke

I don’t have a preference either way as long as all the headers are sent ;)

Co-authored-by: Luke Edwards <luke.edwards05@gmail.com>

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Co-authored-by: Luke Edwards <luke.edwards05@gmail.com>

packages/send-type/index.js

@@ -12,7 +12,10 @@ module.exports = function (res, code=200, data='', headers={}) {
 	let type = obj[TYPE] || res.getHeader(TYPE);
 
 	if (!!data && typeof data.pipe === 'function') {
-		res.setHeader(TYPE, type || OSTREAM);
+		obj[TYPE] = type || OSTREAM;
+		for (k in obj) {
+		  res.setHeader(k, obj[k]);
+		}
 		return data.pipe(res);
 	}