All blue boxes are 100x100px with box-sizing: border-box and 2px border (4px border-top), we expect offsetWidth/Height to be 100x100

### flex-flow: default, orange box has width: 300px

### flex-flow: default, orange box has width: 400px

### flex-flow: default, orange box has width: auto

### flex-flow: default, orange box has width: auto, flex-box has box-sizing: border-box

### flex-flow: column, red box has height: 300px

### flex-flow: column, red box has height: 400px

### flex-flow: column, red box has height: auto

### flex-box has box-sizing: border-box and flex-wrap: wrap;

### flex-box has box-sizing: default and flex-wrap: wrap;

### flex-flow: column, flex-box has box-sizing: border-box, flex items have flex: 1