Bug 130495 Get rid of SessionHandleAdapter
Now, we use SessionHandleAdapter to keep current active report deisng. That's a bad practive for editor swith and rebuild will cuase lots of problmes. Need find way to replace it.
UI/org.eclipse.birt.report.designer.ui.ide/src/org/eclipse/birt/report/designer/ui/editors/ReportEditorProxy.java
IPartListener,
		IPropertyListener,
		IReportEditor
{
	MultiPageReportEditor instance;
	private String title = "";
	public IEditorInput getEditorInput( )
	{
		return instance.getEditorInput( );
	}
	public IEditorSite getEditorSite( )
	{
		return instance.getEditorSite( );
	}
	public void init( IEditorSite site, IEditorInput input )