Relay compiler - No operation text / No operation provided

So I just want to point out that the following issue has been annoying me for the past hour.

```
RelayNetwork: No data returned for operation `CreateRequestScreenMutation`, got error(s):
no operation provided

See the error `source` property for more information.
```

When generating the GraphQL code. the compiler passes with no errors however it is always 1 operation text short.

`[INFO] [default] compiled documents: 5 reader, 5 normalization, 4 operation text`

I found out that it is escaping any GraphQL schema listed under
`extend type Mutation`

I moved that specific mutation under
`type Mutation`

and it successfully generated the operation text and works perfectly now.
feels like a bug that should be addressed as they should both be treated the same.

thanks Relay Team.