gddo-server: fix typos/compile errors from previous commit

Change-Id: Id322ec04be435dc5cccf9e43e527504d0508db76
Reviewed-on: https://go-review.googlesource.com/25542
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/gddo-server/main.go b/gddo-server/main.go
index 17b6205..869ca6c 100644
--- a/gddo-server/main.go
+++ b/gddo-server/main.go
@@ -390,7 +390,7 @@
 			"hide":          hide,
 		})
 	case isView(req, "play"):
-		u, err := playURL(pdoc, req.Form.Get("play"), r.Header.Get("X-AppEngine-Country"))
+		u, err := playURL(pdoc, req.Form.Get("play"), req.Header.Get("X-AppEngine-Country"))
 		if err != nil {
 			return err
 		}
diff --git a/gddo-server/play.go b/gddo-server/play.go
index 90268a2..8e1b149 100644
--- a/gddo-server/play.go
+++ b/gddo-server/play.go
@@ -60,10 +60,11 @@
 func playURL(pdoc *doc.Package, id, countryHeader string) (string, error) {
 	if m := exampleIDPat.FindStringSubmatch(id); m != nil {
 		if e := findExample(pdoc, m[1], m[2], m[3]); e != nil && e.Play != "" {
-			req, err := http.NewRequest("POST", "https://play.golang.org/share", "text/plain", strings.NewReader(e.Play))
+			req, err := http.NewRequest("POST", "https://play.golang.org/share", strings.NewReader(e.Play))
 			if err != nil {
 				return "", err
 			}
+			req.Header.Set("Content-Type", "text/plain")
 			if countryHeader != "" {
 				// Forward the App Engine country header.
 				req.Header.Set("X-AppEngine-Country", countryHeader)