Minor fixes to reduce copying.

PiperOrigin-RevId: 616927443

internal/platform/implementation/wifi_lan.h

@@ -17,6 +17,7 @@
 
 #include <string>
 
+#include "absl/functional/any_invocable.h"
 #include "internal/platform/cancellation_flag.h"
 #include "internal/platform/input_stream.h"
 #include "internal/platform/listeners.h"
@@ -99,10 +100,10 @@ class WifiLanMedium {
 
   // Callback that is invoked when a discovered service is found or lost.
   struct DiscoveredServiceCallback {
-    absl::AnyInvocable<void(NsdServiceInfo service_info)>
-        service_discovered_cb = DefaultCallback<NsdServiceInfo>();
-    absl::AnyInvocable<void(NsdServiceInfo service_info)> service_lost_cb =
-        DefaultCallback<NsdServiceInfo>();
+    absl::AnyInvocable<void(const NsdServiceInfo& service_info)>
+        service_discovered_cb = DefaultCallback<const NsdServiceInfo&>();
+    absl::AnyInvocable<void(const NsdServiceInfo& service_info)>
+        service_lost_cb = DefaultCallback<const NsdServiceInfo&>();
   };
 
   // Starts the discovery of nearby WifiLan services.

internal/platform/nsd_service_info.h

@@ -63,7 +63,7 @@ class NsdServiceInfo {
 
   // Sets all TXTRecord.
   void SetTxtRecords(
-      absl::flat_hash_map<std::string, std::string>& txt_records) {
+      const absl::flat_hash_map<std::string, std::string>& txt_records) {
     txt_records_ = txt_records;
   }
 

internal/platform/wifi_lan.cc

@@ -43,7 +43,7 @@ bool WifiLanMedium::StartDiscovery(const std::string& service_id,
   }
   api::WifiLanMedium::DiscoveredServiceCallback api_callback = {
       .service_discovered_cb =
-          [this](NsdServiceInfo service_info) {
+          [this](const NsdServiceInfo& service_info) {
             MutexLock lock(&mutex_);
             std::string service_type = service_info.GetServiceType();
             // Check callback for the service type.
@@ -86,7 +86,7 @@ bool WifiLanMedium::StartDiscovery(const std::string& service_id,
             medium_callback.service_discovered_cb(service_info, service_id);
           },
       .service_lost_cb =
-          [this](NsdServiceInfo service_info) {
+          [this](const NsdServiceInfo& service_info) {
             MutexLock lock(&mutex_);
             std::string service_type = service_info.GetServiceType();
             std::string service_name = service_info.GetServiceName();