Problem. Today some build scripts in depot tools (e.g. apply_issue.bat [1]) expect its depot_tools dir to provision python/git. Other build scripts may be expecting the depot_tools in $PATH to provision git or python. In both cases, they do it because historically git/python in $PATH may not exist or may be old because we don't update git/python on machines.
Soltuion. Build CIPD packages for python and git, install (ensure) them during build bootstrap, e.g. annotated_run.py, remote_run.py, kitchen-level and make them available in $PATH, so that git/python in $PATH are always safe to use.
The motivation is make win_chromium_rel_ng work on LUCI. Today it does not work because unlike buildbot where depot_tools is updated as as part of update_scripts step, on LUCI the depot_tools in $PATH is old; and we cannot insert recipe-pinned depot_tools into the beginning of $PATH because it is expected to have git/python, which it does not. Fixing this bug will remove the expectation. Once done, we will insert the recipe-pinned depot_tools to the beginning of $PATH.
[1]: https://cs.chromium.org/chromium/tools/depot_tools/apply_issue.bat?dr=C&q=apply_issu&l=11
Comment 1 by no...@chromium.org
, Apr 24 2017