function _ariaLabelledByChanged(sId, sMutation) {

		// forward to all content controls (internal and external
		const aContent = this.getAggregation("_content", []);
		let oContent = this.getContent();
		if (oContent) {
			aContent.push(oContent);
		}

		oContent = this.getContentDisplay();
		if (oContent) {
			aContent.push(oContent);
		}

		oContent = this.getContentEdit();
		if (oContent) {
			aContent.push(oContent);
		}

		for (let i = 0; i < aContent.length; i++) {
			oContent = aContent[i];
			if (oContent.getMetadata().getAllAssociations().ariaLabelledBy) {
				if (sMutation === "remove") {
					oContent.removeAriaLabelledBy(sId);
				} else if (sMutation === "insert") {
					oContent.addAriaLabelledBy(sId);
				}
			}
		}

	}
Required by the {@link sap.m.IOverflowToolbarContent} interface.
Registers invalidations event that is fired when width of the control is changed.

@protected
@returns {object} Configuration information for the <code>sap.m.IOverflowToolbarContent</code> interface.