fnSetOverlayFocusability = (bFocusable) => {
			this.aFocusableOverlays.forEach(function(oOverlay) {
				oOverlay.setFocusable(bFocusable);
			});
		}
Triggers the mode switch (on/off).

@param {sap.ui.base.ManagedObject} oRootControl - Root control of the overlays
@param {sap.ui.rta.toolbar.Adaptation} oToolbar - Toolbar of RTA