Fix destruction of favorites when media is deleted

I'm not sure this will work perfectly, but it should.
I totally agree, I didn't do the other side of the relation though.


Honestly, we need to rename a lot of these poly relations to "media"

On Sun, Jul 20, 2014 at 10:54 PM, Vikhyat Korrapati
<notifications@github.com> wrote:

>>    has_many :castings, dependent: :destroy, as: :castable
>> +  has_many :favorites, dependent: :destroy, as: :item
> Maybe "media" would be a better name than "item" here?
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> https://github.com/hummingbird-me/hummingbird/pull/168/files#r15155700