src/vs/editor/browser/viewParts/lines/viewLine.ts/ViewLine/monospaceAssumptionsAreValid
class ViewLine:	public monospaceAssumptionsAreValid(): boolean {
		if (!this._renderedViewLine) {
			return monospaceAssumptionsAreValid;
		}
		if (this._renderedViewLine instanceof FastRenderedViewLine) {
			return this._renderedViewLine.monospaceAssumptionsAreValid();
		}
		return monospaceAssumptionsAreValid;
	}