driver: use pprof --unit=byte instead of --show_bytes

pprof no longer supports the --show_bytes flag

Change-Id: I2381a1bab374f74b963a168b859182a3b6833ca9
Reviewed-on: https://go-review.googlesource.com/1288

driver/driver.go

diff --git a/driver/driver.go b/driver/driver.go
index b42b1d6..d58c523 100644
--- a/driver/driver.go
+++ b/driver/driver.go
@@ -190,7 +190,7 @@
 		res.Files["cpuprof"] = cpuprof
 	}
 
-	memprof := processProfile("--lines", "--show_bytes", "--alloc_space", "--base", res.Files["memprof0"], os.Args[0], res.Files["memprof"])
+	memprof := processProfile("--lines", "--unit=byte", "--alloc_space", "--base", res.Files["memprof0"], os.Args[0], res.Files["memprof"])
 	delete(res.Files, "memprof")
 	delete(res.Files, "memprof0")
 	if memprof != "" {