Fix another uninitialized bool member bug found by -fsanitize=bool. This one

appears to currently be benign (we happen to test the flags in the right
order, so we never depend on the uninitialized value).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170640 91177308-0d34-0410-b5e6-96231b3b80d8