Members declared in mixins are treated as if these were declared in
the class where they are mixed in. This means that use their types as
declared types, instead of including them in a combined member signature.
This failed in the case where a member was synthetically added to the
mixin class, because the types of these we wrongfully be handled as
declared types.
We now skip all synthetic members when reasoning about mixed in members
as declared members.
Change-Id: I9c2311b4472fe16162fcdc4c56fce8db2d946f4d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/181201
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>
Commit-Queue: Johnni Winther <johnniwinther@google.com>
Johnni Winther
019ce33409