function writeWidthIfContentOccupiesWholeArea(sArea, oRm, oControl) {
		var bContentLeft = !!oControl.getContentLeft().length,
			bContentMiddle = !!oControl.getContentMiddle().length,
			bContentRight = !!oControl.getContentRight().length;
		switch (sArea.toLowerCase()) {
			case "left":
				if (bContentLeft && !bContentMiddle && !bContentRight) {
					oRm.style("width", "100%");
				}
				break;
			case "middle":
				if (bContentMiddle && !bContentLeft && !bContentRight) {
					oRm.style("width", "100%");
				}
				break;
			case "right" :
				if (bContentRight && !bContentLeft && !bContentMiddle) {
					oRm.style("width", "100%");
				}
				break;
			default:
				Log.error("Cannot determine which of the three content aggregations is alone");
		}
	}
Adds width style to 100% in case of the given content container is the only container with content amongst the three (left, middle, right)
@param {string} sArea The content container - one of the left, middle or right
@param {sap.ui.core.RenderManager} oRm The RenderManager that can be used for writing to the Render-Output-Buffer.
@param {sap.m.Bar} oControl the Bar instance
@private