Bug 166015 Refactor designer actions to eclipse command framework
Eclipse command framework provide a more explicit way to manage UI actions contributions, we can take it's advantage to make our actions code more clean and maintainable.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/editors/parts/GraphicalEditorWithFlyoutPalette.java
{
		/**
		 * Constructor
		 * 
		 * @param provider
		 *            the provider used to create a PaletteViewer
		 */
		public CustomPalettePage( PaletteViewerProvider provider )
		{
			super( provider );
		}
		/**
		 * @see org.eclipse.ui.part.IPage#createControl(org.eclipse.swt.widgets.Composite)
		 */
		public void createControl( Composite parent )
		{
			super.createControl( parent );
			if ( splitter != null )
				splitter.setExternalViewer( viewer );
		}
		/**