Indentation parse error with GADTs

Parse error on valid syntax. Given,

```
{-# LANGUAGE GADTs #-}
{-# LANGUAGE StandaloneDeriving #-}

data Bar a where
Bar :: Show a => {
getStr' :: String,
getData' :: a, -- can Show
getInt' :: Int
} -> Bar a -- have (Show a)
deriving instance Show (Bar a)
```

haskell-mode is telling me there is parse error at the `{`

Snippet from http://stackoverflow.com/questions/21505975/write-gadt-record-with-constrained-type