isMixableIn abstract method
Return true if this element, assuming that it is within scope, is
able to be mixed-in by classes and enums in the given library.
Implementation
bool isMixableIn(LibraryElement library);
Return true if this element, assuming that it is within scope, is
able to be mixed-in by classes and enums in the given library.
bool isMixableIn(LibraryElement library);