sidePanel31Splitter.dragAndDrop(0, 100);
sidePanel1.assertExpressionEquals("offsetHeight", 50);
sidePanel2.assertExpressionEquals("offsetHeight", 50);
sidePanel3.assertExpressionEquals("offsetHeight", 50);
sidePanel4.assertExpressionEquals("offsetHeight", 50);
sidePanel31Splitter.dragAndDrop(0, 20);
sidePanel1.assertExpressionEquals("offsetHeight", 50);
sidePanel2.assertExpressionEquals("offsetHeight", 30);
sidePanel3.assertExpressionEquals("offsetHeight", 50);
sidePanel4.assertExpressionEquals("offsetHeight", 50);
sidePanel31Splitter.dragAndDrop(0, 43);