Remove ScopedAddToTraversalPath

ScopedAddToTraversalPath is an RAII wrapper that copies the existing traversal path, modifies it, and then restores the modified properties from the copy when deleted. It's simpler to make the child path a copy and not modify the parent.

Bug: 403312802
Flag: EXEMPT refactor
Test: presubmits
Change-Id: I8f06ed557f29444be6df51c1c8ea60958a82ee95