CL 612617 did speedup RuneCountInString, thus we can now use it to
speedup RuneCount, too.
name old time/op new time/op delta
RuneCountTenASCIIChars-8 8.69ns ± 1% 3.59ns ± 2% -58.66% (p=0.000 n=9+9)
RuneCountTenJapaneseChars-8 49.8ns ± 2% 40.9ns ± 0% -17.94% (p=0.000 n=10+8)
Change-Id: I311750c00efc79af35fb0ca3b482a5d94e0a7977
Reviewed-on: https://go-review.googlesource.com/c/go/+/612955 Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: Tim King <taking@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>