Merge topic 'cxxmodules-export-file-collisions'

4cd153afe3 Merge branch 'backport-cxxmodules-export-file-collisions'
d791f3a180 cxxmodules: make export trampoline script files unique
2352dcc830 Source: Simplify hasher object construction

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: buildbot <buildbot@kitware.com>
Merge-request: !9166