message: use exhaustive struct match for manual Debug impl
diff: @@ -52,9 +52,10 @@ pub struct FrameData<'tcx> {
  impl<'tcx> std::fmt::Debug for FrameData<'tcx> {
  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
  // Omitting `timing`, it does not support `Debug`.
  + let FrameData { call_id, catch_unwind, timing: _ } = self;
  f.debug_struct("FrameData")
  - .field("call_id", &self.call_id)
  - .field("catch_unwind", &self.catch_unwind)
  + .field("call_id", call_id)
  + .field("catch_unwind", catch_unwind)
  .finish()
  }
  }
  