Revert "Use aliases for more constructors and destructors."

This reverts commit r192300.

The change itself looks correct, but it found issues on how we handle aliases
in llvm.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@192353 91177308-0d34-0410-b5e6-96231b3b80d8