general: Use deducation guides for std::lock_guard and std::unique_lock

Since C++17, the introduction of deduction guides for locking facilities
means that we no longer need to hardcode the mutex type into the locks
themselves, making it easier to switch mutex types, should it ever be
necessary in the future.

src/network/room_member.cpp

@@ -157,7 +157,7 @@ bool RoomMember::RoomMemberImpl::IsConnected() const {
 void RoomMember::RoomMemberImpl::MemberLoop() {
     // Receive packets while the connection is open
     while (IsConnected()) {
-        std::lock_guard<std::mutex> lock(network_mutex);
+        std::lock_guard lock(network_mutex);
         ENetEvent event;
         if (enet_host_service(client, &event, 100) > 0) {
             switch (event.type) {
@@ -245,7 +245,7 @@ void RoomMember::RoomMemberImpl::MemberLoop() {
             }
         }
         {
-            std::lock_guard<std::mutex> lock(send_list_mutex);
+            std::lock_guard lock(send_list_mutex);
             for (const auto& packet : send_list) {
                 ENetPacket* enetPacket = enet_packet_create(packet.GetData(), packet.GetDataSize(),
                                                             ENET_PACKET_FLAG_RELIABLE);
@@ -263,7 +263,7 @@ void RoomMember::RoomMemberImpl::StartLoop() {
 }
 
 void RoomMember::RoomMemberImpl::Send(Packet&& packet) {
-    std::lock_guard<std::mutex> lock(send_list_mutex);
+    std::lock_guard lock(send_list_mutex);
     send_list.push_back(std::move(packet));
 }
 
@@ -318,7 +318,7 @@ void RoomMember::RoomMemberImpl::HandleRoomInformationPacket(const ENetEvent* ev
         packet >> member.avatar_url;
 
         {
-            std::lock_guard<std::mutex> lock(username_mutex);
+            std::lock_guard lock(username_mutex);
             if (member.nickname == nickname) {
                 username = member.username;
             }
@@ -473,7 +473,7 @@ RoomMember::RoomMemberImpl::Callbacks::Get() {
 
 template <typename T>
 void RoomMember::RoomMemberImpl::Invoke(const T& data) {
-    std::lock_guard<std::mutex> lock(callback_mutex);
+    std::lock_guard lock(callback_mutex);
     CallbackSet<T> callback_set = callbacks.Get<T>();
     for (auto const& callback : callback_set)
         (*callback)(data);
@@ -482,7 +482,7 @@ void RoomMember::RoomMemberImpl::Invoke(const T& data) {
 template <typename T>
 RoomMember::CallbackHandle<T> RoomMember::RoomMemberImpl::Bind(
     std::function<void(const T&)> callback) {
-    std::lock_guard<std::mutex> lock(callback_mutex);
+    std::lock_guard lock(callback_mutex);
     CallbackHandle<T> handle;
     handle = std::make_shared<std::function<void(const T&)>>(callback);
     callbacks.Get<T>().insert(handle);
@@ -512,7 +512,7 @@ const std::string& RoomMember::GetNickname() const {
 }
 
 const std::string& RoomMember::GetUsername() const {
-    std::lock_guard<std::mutex> lock(room_member_impl->username_mutex);
+    std::lock_guard lock(room_member_impl->username_mutex);
     return room_member_impl->username;
 }
 
@@ -663,7 +663,7 @@ RoomMember::CallbackHandle<Room::BanList> RoomMember::BindOnBanListReceived(
 
 template <typename T>
 void RoomMember::Unbind(CallbackHandle<T> handle) {
-    std::lock_guard<std::mutex> lock(room_member_impl->callback_mutex);
+    std::lock_guard lock(room_member_impl->callback_mutex);
     room_member_impl->callbacks.Get<T>().erase(handle);
 }