Revert "Revert "Basic structural redefinition support""

This reverts commit 5a2301d897294ff4ee6de71f459dc2566dc3fa1a.

Bug: 134162467

Reason for revert: Relanding as unclear if issue is due to topic.

Change-Id: Ib1d1cf2e9132e30c9649b760ae9ae2d8ceacf843
101 files changed