With the original DAG hash, we did not store build dependencies in the database, but
with the full DAG hash, we do. Previously, we'd never tell the concretizer about build
dependencies of things used by hash, because we never had them. Now, we have to avoid
telling the concretizer about them, or they'll unnecessarily constrain build
dependencies for new concretizations.
- [x] Make database track all dependencies included in the `dag_hash`
- [x] Modify spec_clauses so that build dependency information is optional
and off by default.
- [x] `spack diff` asks `spec_clauses` for build dependencies for completeness
- [x] Modify `concretize.lp` so that reuse optimization doesn't affect fresh
installations.
- [x] Modify concretizer setup so that it does *not* prioritize installed versions
over package versions. We don't need this with reuse, so they're low priority.
- [x] Fix `test_installed_deps` for full hash and new concretizer (does not work
for old concretizer with full hash -- leave this for later if we need it)
- [x] Move `test_installed_deps` mock packages to `builtin.mock` for easier debugging
with `spack -m`.
- [x] Fix `test_reuse_installed_packages_when_package_def_changes` for full hash
521c206030