Made LLDB build with the latest Clang.  This meant
changing the ClangASTSource to return a bool instead
of returning a list of results.  Our testsuite mostly
works with this change, but some minor issues may
remain both on LLDB's side and on Clang's side.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@174949 91177308-0d34-0410-b5e6-96231b3b80d8