code review 60070044: bench: move benchmarks from other repo

driver/driver_go12.go

Index: driver/driver_go12.go
===================================================================
new file mode 100644
--- /dev/null
+++ b/driver/driver_go12.go
@@ -0,0 +1,17 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.2
+
+package driver
+
+import (
+	"runtime"
+)
+
+// New mem stats added in Go1.2
+func collectGo12MemStats(res *Result, mstats0, mstats1 *runtime.MemStats) {
+	res.Metrics["sys-gc"] = mstats1.GCSys
+	res.Metrics["sys-other"] = mstats1.OtherSys + mstats1.MSpanSys + mstats1.MCacheSys + mstats1.BuckHashSys
+}