Fix a crash-on-invalid.

Much to everyone's surprise, the default constructor for TypeResult produces
an instance with Invalid == false. This seems like a decision we may want to
revisit.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@138601 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed