tree 58d6ce8801e2a4de04894528fe302de0765a3ad7
parent 7e0a9f67f1ebe9db9459a651d20728467fc8aa7f
author Matt Stark <msta@google.com> 1788394448 +1000
committer gn-scoped@luci-project-accounts.iam.gserviceaccount.com <gn-scoped@luci-project-accounts.iam.gserviceaccount.com> 1788405779 -0700

When re-running build/gen.py from ninja, preserve environment variables.

This ensures that when you run:
```
CXX=PATH_TO_CXX build/gen.py ...
ninja -C out
```

PATH_TO_CXX is actually used when building

Change-Id: Ie9b7fb149bd37181e7e1ba76024a9a806a6a6964
Reviewed-on: https://gn-review.googlesource.com/c/gn/+/26180
Reviewed-by: Takuto Ikuta <tikuta@google.com>
Commit-Queue: Matt Stark <msta@google.com>