Remove @cpp.GenerateTypedInterceptor and associated codegen

Summary: Typed interceptors (aka `ServiceMethodDecorator`) is taking a backseat while we revisit the approach. Let's clean up this unused code.

Reviewed By: thedavekwon

Differential Revision: D54316280

fbshipit-source-id: 49c5a0e93216e1b267ce743fd760741a0123e481

thrift/annotation/cpp.thrift

@@ -338,29 +338,6 @@ struct Frozen2Exclude {}
 @scope.Typedef
 struct Frozen2RequiresCompleteContainerParams {}
 
-/**
- * Generates typed interceptor stubs that can be overriden by user,
- * and adorn the handler methods. This can be used on individual functions
- * or on services (equivalent to adding it to all functions).
- *
- *   service MyService {
- *     @cpp.GenerateTypedInterceptor
- *     void ping();
- *   }
- *
- * This will generate the following interface:
- *
- *   class TypedInterceptor<MyService> {
- *     TypeErasedStorage before_ping();
- *     TypeErasedStorage after_ping();
- *   }
- *
- */
-@scope.Service
-@scope.Interaction
-@scope.Function
-struct GenerateTypedInterceptor {}
-
 /**
  * Causes C++ handler code to run inline on the EventBase thread.
  * Disables overload protection, use with caution.