Bug 302791 [CommonNavigator] Associated editor does not close when deleting resource (editorInput) through CommonNavigator
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/actions/CommonActionProviderDescriptor.java
return false;
		} else if (!visibilityId.equals(other.visibilityId))
			return false;
		return true;
	} 
	
	 
	protected void addDependentDescriptor(
			CommonActionProviderDescriptor dependentDescriptor) {
		Assert.isTrue(this != dependentDescriptor);
		if (dependentDescriptors == null) {
			dependentDescriptors = new LinkedHashSet();
		}
		dependentDescriptors.add(dependentDescriptor);
	}
	protected void addOverridingDescriptor(
			CommonActionProviderDescriptor overridingDescriptor) {
		Assert.isTrue(this != overridingDescriptor);
		if (overridingDescriptors == null) {
			overridingDescriptors = new TreeSet(CommonActionProviderDescriptorCompator.INSTANCE);
		}
		overridingDescriptors.add(overridingDescriptor);
	}
	protected boolean hasDependentDescriptors() {
		return dependentDescriptors != null && !dependentDescriptors.isEmpty();
	}
	protected boolean hasOverridingDescriptors() {
		return overridingDescriptors != null
				&& !overridingDescriptors.isEmpty();
	}