c-index-test: Split "function scanning" behavior into its own "filter" -- its
quite slow and doesn't really stress the APIs people should really use.
 - I'm not even sure if this mode is still useful given the other scanning mode;
   Steve?

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@90193 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed