         if (!layoutTarget)
             return;
             
-        var cw:Number = !isNaN(layoutTarget.explicitWidth) ? layoutTarget.explicitWidth : 
-                                                             layoutTarget.estimatedWidth;
-        var ch:Number = !isNaN(layoutTarget.explicitHeight) ? layoutTarget.explicitHeight : 
-                                                              layoutTarget.estimatedHeight;
-        updateActualValues(cw, ch);
+        updateActualValues(layoutTarget.explicitWidth, layoutTarget.explicitHeight);
 
         // For measure, any explicit overrides for rowCount and columnCount take precedence
         var columnCount:int = _requestedColumnCount != -1 ? Math.max(1, _requestedColumnCount) : _columnCount;

            layoutTarget.invalidateDisplayList();
    }

    /**
     *  @private
     */
	override public function setEstimatedSize(estimatedWidth:Number = NaN, 
												estimatedHeight:Number = NaN,
												invalidateSize:Boolean = true):void
    {
		if (invalidateSize)
        	target.invalidateSize();    
    }
    
    /**
     *  @private
     */

        if ((visibleStartIndex != -1) && (visibleEndIndex != -1))
        {
            for (var index:int = visibleStartIndex; index <= visibleEndIndex; index++)
                updateVirtualTileSize(target.getVirtualElementAt(index));
        }
        
        // Make sure that we always have non-NaN values in the cache, even
