Change our silencing of C typedef redefinition handling to what we had
before r69391: typedef redefinition is an error by default, but if
*either* the old or new definition are from a system header, we silence
it.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70177 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed