tree ccc904e8f12902d43e96a25bd0834f3abde4bc13
parent c407e83d0e2cfc75a660445b6fed28ec7ddefb95
author Erik Ernst <eernst@google.com> 1530619711 +0000
committer Erik Ernst <eernst@google.com> 1530619711 +0000

Adjusted errors for FutureOr in class headers

We did not previously prevent `class C implements FutureOr<int> ..` and
similar declarations. However, it offers only very little value to
allow this, and possibly creates some complications. This CL makes all
these subtype relationships a compile-time error.

The wording of the constraint on `\WITH{} clause` was also adjusted to
remove some potential interpretations which are unintended (like
preventing `with List<dynamic>`, which should be OK).

Change-Id: I626c2767befa7a3cb3092b0ba5cb463e9456d431
Reviewed-on: https://dart-review.googlesource.com/63583
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>