src/vs/platform/contextkey/common/contextkey.ts/ContextKeyExpr/_deserializeAndExpression
class ContextKeyExpr:	private static _deserializeAndExpression(serialized: string, strict: boolean): ContextKeyExpression | undefined {
		const pieces = serialized.split('&&');
		return ContextKeyAndExpr.create(pieces.map(p => this._deserializeOne(p, strict)), null);
	}