2250d3988b
`update_engine_version.{ps1|sh}` needs to operate on a foreign
repository.
When flutter is run in a git-hook, these environment variables will
override our git calls location and corrupt the install.
fixes: #165390
Flutter SDK dependency versions
The files in this directory specifies pinned versions of various dependencies of the flutter SDK.
The bin/internal/engine.version file controls where to find compiled artifacts
of the engine. These artifacts are compiled in the Merge Queue for every commit
in the flutter repository.
The bin/internal/flutter_packages.version file specifies the version
of the flutter/packages repository to be used for testing. The
flutter/packages repository isn't an upstream dependency of
flutter/flutter; it is only used as part of the test suite for
verification, and the pinned version here makes sure that tests are
deterministic at each flutter/flutter commit.