When given the -chained-pch option and a previous PCH file, have the PCHWriter emit a CHAINED_METADATA record instead of METADATA, and write a link to the previous file there.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@108014 91177308-0d34-0410-b5e6-96231b3b80d8
4 files changed