[sh/jdk8u] Backport region count/region size fixes

[Aleksey Shipilev]

On 5/27/21 4:10 PM, Zhengyu Gu wrote:
> 8266802:
>     - Fixed new assertion. Cannot format assertion message in 8u.

Oh, yes you can. Use err_msg, like:

  assert(..., err_msg("%s...", ))


-- 
Thanks,
-Aleksey