Add file added in r171484 to CMakelists.txt.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171494 91177308-0d34-0410-b5e6-96231b3b80d8
Let the formatter ignore UnwrappedLines containing errors.

This prevents code like:

namespace {
class Foo {
  Foo(
  };
}  // comment

from causing segfaults (see llvm.org/PR14774).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171495 91177308-0d34-0410-b5e6-96231b3b80d8