message: feat(c-api) `wasm_func_call` handles null pointers.
diff: @@ -150,10 +150,13 @@ pub unsafe extern "C" fn wasm_func_delete(_func: Option<Box<wasm_func_t>>) {}
  #[no_mangle]
  pub unsafe extern "C" fn wasm_func_call(
  - func: &wasm_func_t,
  - args: &wasm_val_vec_t,
  + func: Option<&wasm_func_t>,
  + args: Option<&wasm_val_vec_t>,
  results: &mut wasm_val_vec_t,
  ) -> Option<Box<wasm_trap_t>> {
  + let func = func?;
  + let args = args?;
  +
  let params = args
  .into_slice()
  .map(|slice| {
  