Bug 48939 [WorkingSets] New working set should preselect with UI selection
If I select 3 projects in the package explorer, then create a new working set, it would be nice if the working set dialog would have those 3 projects preselected. Or if there were a "Create working set" action from the selection in the view.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/dialogs/ResourceWorkingSetPage.java
String title, String message) {
        IStatus status = exception.getStatus();
        if (status != null) {
            ErrorDialog.openError(shell, title, message, status);
        } else {
            MessageDialog
                    .openError(
                            shell,
                            IDEWorkbenchMessages.InternalError, exception.getLocalizedMessage());
        }
    }
    /**
     * Sets the checked state of tree items based on the initial 
     * working set, if any.
     */
    private void initializeCheckedState() {
        if (workingSet == null) {
			return;
		}
        BusyIndicator.showWhile(getShell().getDisplay(), new Runnable() {
            public void run() {
                IAdaptable[] items = workingSet.getElements();
                tree.setCheckedElements(items);
                for (int i = 0; i < items.length; i++) {
                    IAdaptable item = items[i];
                    IContainer container = null;
                    IResource resource = null;
                    if (item instanceof IContainer) {
                        container = (IContainer) item;
                    } else {