This CL restores the equality related tests in
tests/language/closure/identity_equality_tearoff_test.dart that we had
in https://dart-review.googlesource.com/c/sdk/+/202243, but removed
in order to finalize language team discussions about equality of
function objects, based on language issue #1712.
Note that these additional test cases do not include any cases involving
tearoffs of extension methods, they will be dealt with separately.
Change-Id: I84daaf91229bd0d0f4c64446bb71cb87f32eedfc
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/205081
Commit-Queue: Erik Ernst <eernst@google.com>
Reviewed-by: Lasse R.H. Nielsen <lrn@google.com>