os: opening an existing file with O_CREATE|O_TRUNC and permission 0 changes file to be read-only on Windows [1.14 backport] #39158
Description
@ianlancetaylor requested issue #38225 to be considered for backport to the next 1.14 minor release.
@gopherbot Please open a backport to 1.14. This is a regression that was introduced in 1.14.