7.6.3 Constant Constructors: The superinitializer that appears, explicitly or implicitly, in the initializer list of a constant constructor must specify a constant constructor of the superclass of the immediately enclosing class or a compile-time error occurs.
12.1 Mixin Application: For each generative constructor named ... an implicitly declared constructor named ... is declared. If Sq is a generative const constructor, and M does not declare any fields, Cq is also a const constructor.
static const CompileTimeErrorCode CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELD = CompileTimeErrorCode( 'CONST_CONSTRUCTOR_WITH_MIXIN_WITH_FIELD', "Const constructor can't be declared for a class with a mixin " "that declares an instance field.", correction: "Try removing the 'const' keyword or " "removing the 'with' clause from the class declaration, " "or removing fields from the mixin class.")