[handshaker API] remove some unused legacy cruft (#35628)

Closes #35628

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/35628 from markdroth:handshaker_cruft_cleanup 8fad55cf42
PiperOrigin-RevId: 600826375

src/core/lib/security/transport/security_handshaker.cc

@@ -671,11 +671,3 @@ void SecurityRegisterHandshakerFactories(CoreConfiguration::Builder* builder) {
 }
 
 }  // namespace grpc_core
-
-grpc_handshaker* grpc_security_handshaker_create(
-    tsi_handshaker* handshaker, grpc_security_connector* connector,
-    const grpc_channel_args* args) {
-  return SecurityHandshakerCreate(handshaker, connector,
-                                  grpc_core::ChannelArgs::FromC(args))
-      .release();
-}

src/core/lib/security/transport/security_handshaker.h

@@ -42,10 +42,4 @@ void SecurityRegisterHandshakerFactories(CoreConfiguration::Builder*);
 
 }  // namespace grpc_core
 
-// TODO(arjunroy): This is transitional to account for the new handshaker API
-// and will eventually be removed entirely.
-grpc_handshaker* grpc_security_handshaker_create(
-    tsi_handshaker* handshaker, grpc_security_connector* connector,
-    const grpc_channel_args* args);
-
 #endif  // GRPC_SRC_CORE_LIB_SECURITY_TRANSPORT_SECURITY_HANDSHAKER_H

src/core/lib/transport/handshaker.cc

@@ -227,11 +227,3 @@ void HandshakeManager::DoHandshake(grpc_endpoint* endpoint,
 }
 
 }  // namespace grpc_core
-
-void grpc_handshake_manager_add(grpc_handshake_manager* mgr,
-                                grpc_handshaker* handshaker) {
-  // This is a transition method to aid the API change for handshakers.
-  grpc_core::RefCountedPtr<grpc_core::Handshaker> refd_hs(
-      static_cast<grpc_core::Handshaker*>(handshaker));
-  mgr->Add(refd_hs);
-}

src/core/lib/transport/handshaker.h

@@ -162,11 +162,4 @@ class HandshakeManager : public RefCounted<HandshakeManager> {
 
 }  // namespace grpc_core
 
-// TODO(arjunroy): These are transitional to account for the new handshaker API
-// and will eventually be removed entirely.
-typedef grpc_core::HandshakeManager grpc_handshake_manager;
-typedef grpc_core::Handshaker grpc_handshaker;
-void grpc_handshake_manager_add(grpc_handshake_manager* mgr,
-                                grpc_handshaker* handshaker);
-
 #endif  // GRPC_SRC_CORE_LIB_TRANSPORT_HANDSHAKER_H