Google was the subject of widespread condemnation and legal action for the mistaken collection of that data (although no action was taken in the UK), and it seems that the controversy has not ended yet. The data should have been deleted as part of some undertakings that Google agreed to comply with following the data breach. The ICO has told Google to provide access to the relevant data for investigation as to whether the undertakings have been breached.
The ICO initially took no action against Google as it did not consider the data breach to be intentional or reckless; however, recent reports have suggested that the software that collected the data was written intentionally for that purpose, and the ICO reopened its investigation into the data breach as a result.