Equality override on equation member returns a constraint

packages/cassowary/lib/equation_member.dart

@@ -15,7 +15,7 @@ abstract class _EquationMember {
 
   Constraint operator <=(_EquationMember m) => asExpression() <= m;
 
-  /* Constraint */ operator ==(_EquationMember m) => asExpression() == m;
+  Constraint operator ==(_EquationMember m) => asExpression() == m;
 
   Expression operator +(_EquationMember m) => asExpression() + m;
 

packages/cassowary/test/cassowary_test.dart

@@ -585,4 +585,11 @@ void main() {
     p.context = "b";
     expect(p.context, "b");
   });
+
+  test('check_type_of_eq_result', () {
+    Param left = new Param();
+    Param right = new Param();
+
+    expect((left == right).runtimeType, Constraint);
+  });
 }