Is this unusual? Even in germany, which has lots of laws protecting (white- and bluecollar) workers this is a reasonable cause to layoff people.
If these employees were not contractors or on a short-term contract, this layoff could easily be contested and Google would have to pay up to 1 month's pay per year worked at Google (minimum 3 month's pays)
Google could have negotiated with the employees to end the contract at a better price.
To widen your perspectives.
laws are rarely idiotic, businesses are
Frankly, I've seen many more idiotic laws than I've seen idiotic businesses.
Belgium isn't much different. I lived and worked there for almost eight years, and I saw this problem in spades from the other side.
IMHO a bad way to treat your workforce.