cmd/heapview: remove needless slash

Change-Id: Ie19a60595862c0afff9364ee21dd9598370e6c91
Reviewed-on: https://go-review.googlesource.com/38752
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/cmd/heapview/main.go b/cmd/heapview/main.go
index 5fab790..b65f52a 100644
--- a/cmd/heapview/main.go
+++ b/cmd/heapview/main.go
@@ -39,7 +39,7 @@
 		log.Println("error: GOPATH not set. Can't find client files")
 		os.Exit(1)
 	}
-	return filepath.Join(filepath.SplitList(gopath)[0], "/src/golang.org/x/tools")
+	return filepath.Join(filepath.SplitList(gopath)[0], "src/golang.org/x/tools")
 }
 
 var parseFlags = func() {