Ninja: Restore support for non-ascii paths on Windows with ninja<=1.10

Revert commit bbdb000c55 (GlobalNinjaGenerator: enlarge file stream
buffer, 2022-01-25, v3.23.0-rc1~68^2).  Somehow `rdbuf()->pubsetbuf()`
is resetting our imbued locale and `cm_codecvt` that handles encoding.

Fixes: #24089
2 files changed