src/vs/editor/contrib/codelens/browser/codelensWidget.ts/CodeLensWidget/computeIfNecessary
class CodeLensWidget:	computeIfNecessary(model: ITextModel): CodeLensItem[] | null {
		if (!this._viewZone.isVisible()) {
			return null;
		}

		// Read editor current state
		for (let i = 0; i < this._decorationIds.length; i++) {
			const range = model.getDecorationRange(this._decorationIds[i]);
			if (range) {
				this._data[i].symbol.range = range;
			}
		}
		return this._data;
	}