According to your source he hasn't made any new laws, he's just setting up a police unit to enforce existing laws.

The existing laws do not say "anybody who posts stuff against muslims on social networks is guilty of a hate crime".

Here's an example of the kind of crime they're talking about: https://www.judiciary.gov.uk/judgments/sentencing-remarks-of...

Here's the criminal prosecution guidance about online hate crime: http://www.cps.gov.uk/legal/a_to_c/communications_sent_via_s...