Illegal constraint in a superclass context (GHC 8.0.1)

Question

So I have this code that throws an error I can't find any information on. Here's the code:

{-# LANGUAGE DataKinds #-}
module Main where
import Network.Google

class ( HasScope '["https://www.googleapis.com/auth/datastore"] a
      , GoogleRequest a) 
      => IsRequest a

Here's the error:

• Illegal constraint ‘HasScope
                    '["https://www.googleapis.com/auth/datastore"]
                    a’ in a superclass context
(Use UndecidableInstances to permit this)
• In the context: (HasScope
                 '["https://www.googleapis.com/auth/datastore"] a,
               GoogleRequest a)
While checking the super-classes of class ‘IsRequest’
In the class declaration for ‘IsRequest’

What's going on here? I'm using GHC 8.0.1.