message: Fix LLDB build.
  It was broken by r318489.
diff: #include "lldb/Utility/Stream.h" // for Stream
  #include "lldb/Utility/StreamString.h"
  #include "llvm/ADT/STLExtras.h" // for make_unique
  +#include "llvm/Support/MemoryBuffer.h"
  #include <cerrno>
  #include <cstdlib>
  #include <inttypes.h>
  