Bug 188283 Bubbles should be z-sorted by size in Bubble charts
Biggest bubbles should be drawn first so that there is no small bubble hidden by a bigger one.
chart/org.eclipse.birt.chart.engine/src/org/eclipse/birt/chart/event/WrappedInstruction.java
},
				ULocale.getDefault( ) );
	}
	/**
	 * @return Returns the mimimum bounds required to contain the rendering area
	 *         of associated rendering event.
	 */
	public final Bounds getBounds( )
	{
		if ( !isModel( ) )
		{
			try
			{
				return pre.getBounds( );
			}
			catch ( Exception ex )
			{
				ex.printStackTrace( );
			}
		}
		else
		{
			Bounds bo = null;
			for ( int i = 0; i < alEvents.size( ); i++ )
			{
				try
				{
					if ( i == 0 )
					{
						bo = ( (PrimitiveRenderEvent) alEvents.get( i ) ).getBounds( );