[FEATURE] sap.m.IconTabBar: Stretch content height, apply content padding &
background design transparent

If property stretchContentHeight is set to true, the Icon Tab Bar
content will get the whole possible height of its parent div.

Change-Id: I39dc2b29025fdb03f1f7ffbc9836388b12823a77
Merge "[FEATURE] sap.m.IconTabBar: Stretch content height, apply content padding & background design transparent"