Changes

Summary

1. A disable checked checkbox can be rendering a checked checkbox. (details)
2. added both methods (details)
3. Fixes #2980 (details)

Commit 55a8a38fffb4fce2ee413eee180c0f669ae3d69d by 570gina A disable checked checkbox can be rendering a checked checkbox.
	src/Polymorph-Widgets/UITheme.class.st (diff)
Commit 49b7d203632c4a4a67782fd4cab1daa183cc60b7 by guerra.dayne added both methods
	src/SUnit-Core/TestAsserter.class.st (diff)
Commit 89630db54d7301e302a826d9596c577811022865 by stephane.ducasse Fixes #2980
	src/Rubric/RubPluggableTextFieldMorph.class.st (diff)