go-tour: use playground package from go.talks for /compile handler

R=golang-dev, dsymonds
CC=golang-dev
https://golang.org/cl/8839044
diff --git a/gotour/appengine.go b/gotour/appengine.go
index a410989..d48c1be 100644
--- a/gotour/appengine.go
+++ b/gotour/appengine.go
@@ -9,19 +9,18 @@
 import (
 	"bufio"
 	"bytes"
-	"fmt"
 	"io"
 	"net/http"
 
 	"appengine"
-	"appengine/urlfetch"
+
+	_ "code.google.com/p/go.talks/pkg/playground"
 )
 
 const runUrl = "http://golang.org/compile"
 
 func init() {
 	http.HandleFunc("/", rootHandler)
-	http.HandleFunc("/compile", compileHandler)
 	err := serveScripts("js", "playground.js")
 	if err != nil {
 		panic(err)
@@ -38,30 +37,6 @@
 	}
 }
 
-func compileHandler(w http.ResponseWriter, r *http.Request) {
-	if err := passThru(w, r); err != nil {
-		w.WriteHeader(http.StatusInternalServerError)
-		fmt.Fprintln(w, "Compile server error.")
-	}
-}
-
-func passThru(w io.Writer, req *http.Request) error {
-	c := appengine.NewContext(req)
-	client := urlfetch.Client(c)
-	defer req.Body.Close()
-	r, err := client.Post(runUrl, req.Header.Get("Content-type"), req.Body)
-	if err != nil {
-		c.Errorf("making POST request:", err)
-		return err
-	}
-	defer r.Body.Close()
-	if _, err := io.Copy(w, r.Body); err != nil {
-		c.Errorf("copying response Body:", err)
-		return err
-	}
-	return nil
-}
-
 // prepContent returns a Reader that produces the content from the given
 // Reader, but strips the prefix "#appengine: " from each line. It also drops
 // any non-blank like that follows a series of 1 or more lines with the prefix.