anchor.diff:            justifyContent: FlexJustifyContent.collapse
           )
         ));
  -      flexSize = tester.findElementByKey(flexKey).renderObject.size;
  -      expect(flexSize.width, equals(40.0));
  -      expect(flexSize.height, equals(100.0));
  +      renderBox = tester.findElementByKey(flexKey).renderObject;
  +      expect(renderBox.size.width, equals(40.0));
  +      expect(renderBox.size.height, equals(100.0));
       });
   
       // Column without justifyContent: FlexJustifyContent.collapse
  
positive.code:           key: flexKey
          )
        ));
        Size flexSize = tester.findElementByKey(flexKey).renderObject.size;
        expect(flexSize.width, equals(800.0));
        expect(flexSize.height, equals(100.0));
  
        // Row with justifyContent: FlexJustifyContent.collapse
        tester.pumpWidget(new Center(
  
negative.code:           key: flexKey
          )
        ));
        RenderBox renderBox = tester.findElementByKey(flexKey).renderObject;
        expect(renderBox.size.width, equals(100.0));
        expect(renderBox.size.height, equals(600.0));
  
        // Column with justifyContent: FlexJustifyContent.collapse
        tester.pumpWidget(new Center(
  