Bug 131243 Open invalid report design.
Open a invalid report design should switch to XML Source editor page and can't switch to other pages, when the source is correct user can switch to layout and other pages.
UI/org.eclipse.birt.report.designer.ui.editors/src/org/eclipse/birt/report/designer/ui/editors/MultiPageReportEditor.java
* (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.forms.editor.FormEditor#dispose()
	 */
	public void dispose( )
	{
		getSite( ).getWorkbenchWindow( )
				.getPartService( )
				.removePartListener( this );
		DataSetManager.removeInstance( this.getEditorInput( ) );
		if ( fPalettePage != null )
		{
			fPalettePage.dispose( );
		}
		if ( outlinePage != null )
		{
			outlinePage.dispose( );
		}
		if ( dataPage != null )
		{
			dataPage.dispose( );
		}
		super.dispose( );
	}
	public IEditorPart getEditorPart( )
	{
		return this;
	}
}