Revert "Trimmed the branch to only the 3rdparty/downward sub directory"

This reverts commit f29a74feb79adbdc886bce3a5e21b31f5a4c8da8.
Rebase from 'upstream'
Trimmed the branch to only the 3rdparty/downward sub directory
Revert "Trimmed the branch to only the 3rdparty/downward sub directory"

This reverts commit 2fac8edce0fc547cfa7d645bb968e62ed1e16382.
Rebase from 'upstream' (no changes)
Trimmed the branch to only the 3rdparty/downward sub directory