net/http/pprof: attach handlers using http.HandleFunc

Simplify how pprof attaches the handlers to the DefaultMux by using
http.HandleFunc instead of manually wrapping the handlers in
a http.HandlerFunc.

Change-Id: I65db262ebb2e29e4b6f30df9d2688f5daf782c29
Reviewed-on: https://go-review.googlesource.com/71251Reviewed-by: Sam Whited <sam@samwhited.com>
Reviewed-by: Tom Bergan <tombergan@google.com>
Run-TryBot: Sam Whited <sam@samwhited.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/net/http/pprof/pprof.go

@@ -69,11 +69,11 @@ import (
 )
 
 func init() {
-	http.Handle("/debug/pprof/", http.HandlerFunc(Index))
-	http.Handle("/debug/pprof/cmdline", http.HandlerFunc(Cmdline))
-	http.Handle("/debug/pprof/profile", http.HandlerFunc(Profile))
-	http.Handle("/debug/pprof/symbol", http.HandlerFunc(Symbol))
-	http.Handle("/debug/pprof/trace", http.HandlerFunc(Trace))
+	http.HandleFunc("/debug/pprof/", Index)
+	http.HandleFunc("/debug/pprof/cmdline", Cmdline)
+	http.HandleFunc("/debug/pprof/profile", Profile)
+	http.HandleFunc("/debug/pprof/symbol", Symbol)
+	http.HandleFunc("/debug/pprof/trace", Trace)
 }
 
 // Cmdline responds with the running program's