Relax assertion in ReplaceableMetadataImpl::replaceAllUsesWith().
There is a legitimate use-case in clang where we need to replace a
temporary placeholder node with the temporary node that may be a
forward declaration.

<rdar://problem/24493203>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@259973 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed