commit ba2417fdc026629a29f9fe3ac059aaa831483a33
author Paul Berry <paulberry@google.com> Mon Dec 11 13:02:19 2017 +0000
committer Paul Berry <paulberry@google.com> Mon Dec 11 13:02:19 2017 +0000
tree cacffa07c6517e578013b3be7a2451136ea8e134
parent 50865e93876c9b87ae2c65f009145e4fdeca878f

Fix SDK errors due to inconsistent inheritance of Operator==.

The informal spec for strong mode top level inference
(https://github.com/dart-lang/sdk/pull/28218) says "If there are
multiple overridden/implemented methods, and any two of them have
non-equal types (declared or inferred) for a parameter position which
is being inferred for the overriding method, it is an error."

This CL fixes several SDK errors that arise from this rule.  For
example, the classes _Closure, Function, and Object contained members
declared as follows:

    class _Closure implements Function {
      bool operator ==(other) ...
    }
    class Function {
      bool operator ==(Object other) ...
    }
    class Object {
      bool operator ==(other) ...
    }

The type of Object's operator == was (dynamic) -> bool; the type of
Function's operator == was (Object) -> bool; therefore the type of
_Closure's operator == (which overrides both, since _Closure extends
Object and implements Function) cannot be inferred and must be
specified.

A similar situation exists for _Double and _IntegerImplementation
(both implement num, which declares operator == to have type (Object)
-> bool), and _Uri (which implements Uri, which declares operator ==
to have type (Object) -> bool).

This CL fixes the error by specifying the type explicitly in the
classes _Closure, _Double, _IntegerImplementation, and _Uri.

Change-Id: I91f7ceef8549399d438ba4be8c408493b3f338db
Reviewed-on: https://dart-review.googlesource.com/28100
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>