Bug 4373 Packages View - double clich doesn't expand two hiearchy levels
- enable: Show CU children in packages view - double click on CU observe: only one level gets expanded - now expand a node by clicking on the + observe: two levels get expanded
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
/**
 	 * Handles key events in viewer.
 	 */
	void handleKeyPressed(KeyEvent event) {
		if (event.character == SWT.DEL && event.stateMask == 0 && fDeleteAction.isEnabled())
			fDeleteAction.run();
	}
	
	/**
	 * Handles double clicks in viewer.
	 * Opens editor if file double-clicked.
	 */
	private void handleDoubleClick(DoubleClickEvent event) {
		IStructuredSelection s= (IStructuredSelection) event.getSelection();
		Object element= s.getFirstElement();
		
		
		if (EditorUtility.isOpenInEditor(element) == null) {
			if (fOpenCUAction.isEnabled()) {
				fOpenCUAction.run();
				return;
			}
		}
		if (fViewer.isExpandable(element)) {
			if (JavaBasePreferencePage.doubleClockGoesInto())
				fZoomInAction.run();
			else
				fViewer.setExpandedState(element, !fViewer.getExpandedState(element));
		}
	}