Bug 127451 [Mapping] Model provider and working set mappings must be dynamic
The model provider and working set mappings must be dynamic. Currently they use CompositeResourceMapping which means that changes to the projects of the model provider or the contents of the working set get missed if someone holds onto a mapping.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/model/WorkingSetAdapterFactory.java
/*
	 * Adapter for converting a working set to a resource mapping for use by
	 * object contributions.
	 */
	class ContributorResourceAdapter implements IContributorResourceAdapter2 {
		public ResourceMapping getAdaptedResourceMapping(IAdaptable adaptable) {
			if (adaptable instanceof IWorkingSet) {
				IWorkingSet workingSet = (IWorkingSet) adaptable;
				IAdaptable[] elements = workingSet.getElements();
				List result = new ArrayList();
				for (int i = 0; i < elements.length; i++) {
					IAdaptable element = elements[i];
					ResourceMapping mapping = getContributedResourceMapping(element);
					if (mapping == null) {
						mapping = getResourceMapping(element);
					}
					if (mapping != null) {
						result.add(mapping);
					}