function writeRootOpenTag(bPreserve) {
			rm.openStart("div", oControl);
			rm.class("sapUiView");
			rm.class("sapUiXMLView");
			ViewRenderer.addDisplayClass(rm, oControl);
			if (bPreserve) {
				rm.attr("data-sap-ui-preserve", oControl.getId());
			}
			rm.style("width", oControl.getWidth());
			rm.style("height", oControl.getHeight());
			rm.openEnd();
		}
Create the root open tag.

@param {boolean} bPreserve Whether the DOM should be preserved
@ui5-transform-hint replace-param bPreserve false