diff --git a/quic/core/crypto/quic_crypto_client_config.h b/quic/core/crypto/quic_crypto_client_config.h
index b4675de..b28a31a 100644
--- a/quic/core/crypto/quic_crypto_client_config.h
+++ b/quic/core/crypto/quic_crypto_client_config.h
@@ -66,12 +66,10 @@
   // copied. Multiple sessions might need to be inserted for a connection.
   // SessionCache implementations should support storing
   // multiple entries per server ID.
-  // TODO(renjietang): Once params and application_states are wired up, change
-  // the argument type to const&.
   virtual void Insert(const QuicServerId& server_id,
                       bssl::UniquePtr<SSL_SESSION> session,
-                      TransportParameters* params,
-                      ApplicationState* application_states) = 0;
+                      const TransportParameters& params,
+                      const ApplicationState* application_state) = 0;
 
   // Lookup is called once at the beginning of each TLS handshake to potentially
   // provide the saved state both for the TLS handshake and for sending 0-RTT
diff --git a/quic/core/tls_client_handshaker.cc b/quic/core/tls_client_handshaker.cc
index f16fdd5..3770ebd 100644
--- a/quic/core/tls_client_handshaker.cc
+++ b/quic/core/tls_client_handshaker.cc
@@ -520,7 +520,7 @@
     return;
   }
   session_cache_->Insert(server_id_, std::move(session),
-                         received_transport_params_.get(),
+                         *received_transport_params_,
                          received_application_state_.get());
 }
 
@@ -544,11 +544,11 @@
     if (cached_tls_sessions_[1] != nullptr) {
       // Insert the older session first.
       session_cache_->Insert(server_id_, std::move(cached_tls_sessions_[1]),
-                             received_transport_params_.get(),
+                             *received_transport_params_,
                              received_application_state_.get());
     }
     session_cache_->Insert(server_id_, std::move(cached_tls_sessions_[0]),
-                           received_transport_params_.get(),
+                           *received_transport_params_,
                            received_application_state_.get());
   }
 }
diff --git a/quic/test_tools/simple_session_cache.cc b/quic/test_tools/simple_session_cache.cc
index bbb5f28..6a0cafb 100644
--- a/quic/test_tools/simple_session_cache.cc
+++ b/quic/test_tools/simple_session_cache.cc
@@ -11,8 +11,8 @@
 
 void SimpleSessionCache::Insert(const QuicServerId& server_id,
                                 bssl::UniquePtr<SSL_SESSION> session,
-                                TransportParameters* params,
-                                ApplicationState* application_state) {
+                                const TransportParameters& params,
+                                const ApplicationState* application_state) {
   auto it = cache_entries_.find(server_id);
   if (it == cache_entries_.end()) {
     it = cache_entries_.insert(std::make_pair(server_id, Entry())).first;
@@ -24,9 +24,7 @@
     it->second.application_state =
         std::make_unique<ApplicationState>(*application_state);
   }
-  if (params != nullptr) {
-    it->second.params = std::make_unique<TransportParameters>(*params);
-  }
+  it->second.params = std::make_unique<TransportParameters>(params);
 }
 
 std::unique_ptr<QuicResumptionState> SimpleSessionCache::Lookup(
diff --git a/quic/test_tools/simple_session_cache.h b/quic/test_tools/simple_session_cache.h
index 0bb23e0..cfe3f4a 100644
--- a/quic/test_tools/simple_session_cache.h
+++ b/quic/test_tools/simple_session_cache.h
@@ -24,8 +24,8 @@
 
   void Insert(const QuicServerId& server_id,
               bssl::UniquePtr<SSL_SESSION> session,
-              TransportParameters* params,
-              ApplicationState* application_state) override;
+              const TransportParameters& params,
+              const ApplicationState* application_state) override;
   std::unique_ptr<QuicResumptionState> Lookup(const QuicServerId& server_id,
                                               const SSL_CTX* ctx) override;