diff --git a/p2p/base/stun.cc b/p2p/base/stun.cc
index e7d1244..9d76b1c 100644
--- a/p2p/base/stun.cc
+++ b/p2p/base/stun.cc
@@ -52,6 +52,8 @@
   RTC_DCHECK(IsValidTransactionId(transaction_id_));
 }
 
+StunMessage::~StunMessage() = default;
+
 bool StunMessage::IsLegacy() const {
   if (transaction_id_.size() == kStunLegacyTransactionIdLength)
     return true;
@@ -287,7 +289,7 @@
   // it can't fail.
   auto fingerprint_attr_ptr =
       rtc::MakeUnique<StunUInt32Attribute>(STUN_ATTR_FINGERPRINT, 0);
-  auto fingerprint_attr = fingerprint_attr_ptr.get();
+  auto* fingerprint_attr = fingerprint_attr_ptr.get();
   AddAttribute(std::move(fingerprint_attr_ptr));
 
   // Calculate the CRC-32 for the message and insert it.
@@ -386,6 +388,10 @@
   return true;
 }
 
+StunMessage* StunMessage::CreateNew() const {
+  return new StunMessage();
+}
+
 StunAttributeValueType StunMessage::GetAttributeValueType(int type) const {
   switch (type) {
     case STUN_ATTR_MAPPED_ADDRESS:      return STUN_VALUE_ADDRESS;
@@ -524,6 +530,10 @@
     : StunAttribute(type, length) {
 }
 
+StunAttributeValueType StunAddressAttribute::value_type() const {
+  return STUN_VALUE_ADDRESS;
+}
+
 bool StunAddressAttribute::Read(ByteBufferReader* buf) {
   uint8_t dummy;
   if (!buf->ReadUInt8(&dummy))
@@ -597,6 +607,14 @@
     : StunAddressAttribute(type, length), owner_(owner) {
 }
 
+StunAttributeValueType StunXorAddressAttribute::value_type() const {
+  return STUN_VALUE_XOR_ADDRESS;
+}
+
+void StunXorAddressAttribute::SetOwner(StunMessage* owner) {
+  owner_ = owner;
+}
+
 rtc::IPAddress StunXorAddressAttribute::GetXoredIP() const {
   if (owner_) {
     rtc::IPAddress ip = ipaddr();
@@ -678,6 +696,10 @@
     : StunAttribute(type, SIZE), bits_(0) {
 }
 
+StunAttributeValueType StunUInt32Attribute::value_type() const {
+  return STUN_VALUE_UINT32;
+}
+
 bool StunUInt32Attribute::GetBit(size_t index) const {
   RTC_DCHECK(index < 32);
   return static_cast<bool>((bits_ >> index) & 0x1);
@@ -708,6 +730,10 @@
     : StunAttribute(type, SIZE), bits_(0) {
 }
 
+StunAttributeValueType StunUInt64Attribute::value_type() const {
+  return STUN_VALUE_UINT64;
+}
+
 bool StunUInt64Attribute::Read(ByteBufferReader* buf) {
   if (length() != SIZE || !buf->ReadUInt64(&bits_))
     return false;
@@ -744,6 +770,10 @@
   delete [] bytes_;
 }
 
+StunAttributeValueType StunByteStringAttribute::value_type() const {
+  return STUN_VALUE_BYTE_STRING;
+}
+
 void StunByteStringAttribute::CopyBytes(const char* bytes) {
   CopyBytes(bytes, strlen(bytes));
 }
@@ -805,6 +835,10 @@
 StunErrorCodeAttribute::~StunErrorCodeAttribute() {
 }
 
+StunAttributeValueType StunErrorCodeAttribute::value_type() const {
+  return STUN_VALUE_ERROR_CODE;
+}
+
 int StunErrorCodeAttribute::code() const {
   return class_ * 100 + number_;
 }
@@ -853,6 +887,10 @@
   delete attr_types_;
 }
 
+StunAttributeValueType StunUInt16ListAttribute::value_type() const {
+  return STUN_VALUE_UINT16_LIST;
+}
+
 size_t StunUInt16ListAttribute::Size() const {
   return attr_types_->size();
 }
@@ -946,4 +984,79 @@
   return true;
 }
 
+StunAttributeValueType RelayMessage::GetAttributeValueType(int type) const {
+  switch (type) {
+    case STUN_ATTR_LIFETIME:
+      return STUN_VALUE_UINT32;
+    case STUN_ATTR_MAGIC_COOKIE:
+      return STUN_VALUE_BYTE_STRING;
+    case STUN_ATTR_BANDWIDTH:
+      return STUN_VALUE_UINT32;
+    case STUN_ATTR_DESTINATION_ADDRESS:
+      return STUN_VALUE_ADDRESS;
+    case STUN_ATTR_SOURCE_ADDRESS2:
+      return STUN_VALUE_ADDRESS;
+    case STUN_ATTR_DATA:
+      return STUN_VALUE_BYTE_STRING;
+    case STUN_ATTR_OPTIONS:
+      return STUN_VALUE_UINT32;
+    default:
+      return StunMessage::GetAttributeValueType(type);
+  }
+}
+
+StunMessage* RelayMessage::CreateNew() const {
+  return new RelayMessage();
+}
+
+StunAttributeValueType TurnMessage::GetAttributeValueType(int type) const {
+  switch (type) {
+    case STUN_ATTR_CHANNEL_NUMBER:
+      return STUN_VALUE_UINT32;
+    case STUN_ATTR_TURN_LIFETIME:
+      return STUN_VALUE_UINT32;
+    case STUN_ATTR_XOR_PEER_ADDRESS:
+      return STUN_VALUE_XOR_ADDRESS;
+    case STUN_ATTR_DATA:
+      return STUN_VALUE_BYTE_STRING;
+    case STUN_ATTR_XOR_RELAYED_ADDRESS:
+      return STUN_VALUE_XOR_ADDRESS;
+    case STUN_ATTR_EVEN_PORT:
+      return STUN_VALUE_BYTE_STRING;
+    case STUN_ATTR_REQUESTED_TRANSPORT:
+      return STUN_VALUE_UINT32;
+    case STUN_ATTR_DONT_FRAGMENT:
+      return STUN_VALUE_BYTE_STRING;
+    case STUN_ATTR_RESERVATION_TOKEN:
+      return STUN_VALUE_BYTE_STRING;
+    default:
+      return StunMessage::GetAttributeValueType(type);
+  }
+}
+
+StunMessage* TurnMessage::CreateNew() const {
+  return new TurnMessage();
+}
+
+StunAttributeValueType IceMessage::GetAttributeValueType(int type) const {
+  switch (type) {
+    case STUN_ATTR_PRIORITY:
+    case STUN_ATTR_NETWORK_INFO:
+    case STUN_ATTR_NOMINATION:
+      return STUN_VALUE_UINT32;
+    case STUN_ATTR_USE_CANDIDATE:
+      return STUN_VALUE_BYTE_STRING;
+    case STUN_ATTR_ICE_CONTROLLED:
+      return STUN_VALUE_UINT64;
+    case STUN_ATTR_ICE_CONTROLLING:
+      return STUN_VALUE_UINT64;
+    default:
+      return StunMessage::GetAttributeValueType(type);
+  }
+}
+
+StunMessage* IceMessage::CreateNew() const {
+  return new IceMessage();
+}
+
 }  // namespace cricket
diff --git a/p2p/base/stun.h b/p2p/base/stun.h
index 9eb89e6..6ff07b5 100644
--- a/p2p/base/stun.h
+++ b/p2p/base/stun.h
@@ -132,7 +132,7 @@
 class StunMessage {
  public:
   StunMessage();
-  virtual ~StunMessage() = default;
+  virtual ~StunMessage();
 
   int type() const { return type_; }
   size_t length() const { return length_; }
@@ -188,7 +188,7 @@
   bool Write(rtc::ByteBufferWriter* buf) const;
 
   // Creates an empty message. Overridable by derived classes.
-  virtual StunMessage* CreateNew() const { return new StunMessage(); }
+  virtual StunMessage* CreateNew() const;
 
  protected:
   // Verifies that the given attribute is allowed for this message.
@@ -265,9 +265,7 @@
   StunAddressAttribute(uint16_t type, const rtc::SocketAddress& addr);
   StunAddressAttribute(uint16_t type, uint16_t length);
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_ADDRESS;
-  }
+  StunAttributeValueType value_type() const override;
 
   StunAddressFamily family() const {
     switch (address_.ipaddr().family()) {
@@ -293,8 +291,8 @@
   }
   void SetPort(uint16_t port) { address_.SetPort(port); }
 
-  virtual bool Read(rtc::ByteBufferReader* buf);
-  virtual bool Write(rtc::ByteBufferWriter* buf) const;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   void EnsureAddressLength() {
@@ -324,14 +322,10 @@
   StunXorAddressAttribute(uint16_t type, const rtc::SocketAddress& addr);
   StunXorAddressAttribute(uint16_t type, uint16_t length, StunMessage* owner);
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_XOR_ADDRESS;
-  }
-  virtual void SetOwner(StunMessage* owner) {
-    owner_ = owner;
-  }
-  virtual bool Read(rtc::ByteBufferReader* buf);
-  virtual bool Write(rtc::ByteBufferWriter* buf) const;
+  StunAttributeValueType value_type() const override;
+  void SetOwner(StunMessage* owner) override;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   rtc::IPAddress GetXoredIP() const;
@@ -345,9 +339,7 @@
   StunUInt32Attribute(uint16_t type, uint32_t value);
   explicit StunUInt32Attribute(uint16_t type);
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_UINT32;
-  }
+  StunAttributeValueType value_type() const override;
 
   uint32_t value() const { return bits_; }
   void SetValue(uint32_t bits) { bits_ = bits; }
@@ -355,8 +347,8 @@
   bool GetBit(size_t index) const;
   void SetBit(size_t index, bool value);
 
-  virtual bool Read(rtc::ByteBufferReader* buf);
-  virtual bool Write(rtc::ByteBufferWriter* buf) const;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   uint32_t bits_;
@@ -368,15 +360,13 @@
   StunUInt64Attribute(uint16_t type, uint64_t value);
   explicit StunUInt64Attribute(uint16_t type);
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_UINT64;
-  }
+  StunAttributeValueType value_type() const override;
 
   uint64_t value() const { return bits_; }
   void SetValue(uint64_t bits) { bits_ = bits; }
 
-  virtual bool Read(rtc::ByteBufferReader* buf);
-  virtual bool Write(rtc::ByteBufferWriter* buf) const;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   uint64_t bits_;
@@ -389,11 +379,9 @@
   StunByteStringAttribute(uint16_t type, const std::string& str);
   StunByteStringAttribute(uint16_t type, const void* bytes, size_t length);
   StunByteStringAttribute(uint16_t type, uint16_t length);
-  ~StunByteStringAttribute();
+  ~StunByteStringAttribute() override;
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_BYTE_STRING;
-  }
+  StunAttributeValueType value_type() const override;
 
   const char* bytes() const { return bytes_; }
   std::string GetString() const { return std::string(bytes_, length()); }
@@ -404,8 +392,8 @@
   uint8_t GetByte(size_t index) const;
   void SetByte(size_t index, uint8_t value);
 
-  virtual bool Read(rtc::ByteBufferReader* buf);
-  virtual bool Write(rtc::ByteBufferWriter* buf) const;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   void SetBytes(char* bytes, size_t length);
@@ -419,11 +407,9 @@
   static const uint16_t MIN_SIZE;
   StunErrorCodeAttribute(uint16_t type, int code, const std::string& reason);
   StunErrorCodeAttribute(uint16_t type, uint16_t length);
-  ~StunErrorCodeAttribute();
+  ~StunErrorCodeAttribute() override;
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_ERROR_CODE;
-  }
+  StunAttributeValueType value_type() const override;
 
   // The combined error and class, e.g. 0x400.
   int code() const;
@@ -437,8 +423,8 @@
   void SetNumber(uint8_t number) { number_ = number; }
   void SetReason(const std::string& reason);
 
-  bool Read(rtc::ByteBufferReader* buf);
-  bool Write(rtc::ByteBufferWriter* buf) const;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   uint8_t class_;
@@ -450,19 +436,17 @@
 class StunUInt16ListAttribute : public StunAttribute {
  public:
   StunUInt16ListAttribute(uint16_t type, uint16_t length);
-  ~StunUInt16ListAttribute();
+  ~StunUInt16ListAttribute() override;
 
-  virtual StunAttributeValueType value_type() const {
-    return STUN_VALUE_UINT16_LIST;
-  }
+  StunAttributeValueType value_type() const override;
 
   size_t Size() const;
   uint16_t GetType(int index) const;
   void SetType(int index, uint16_t value);
   void AddType(uint16_t value);
 
-  bool Read(rtc::ByteBufferReader* buf);
-  bool Write(rtc::ByteBufferWriter* buf) const;
+  bool Read(rtc::ByteBufferReader* buf) override;
+  bool Write(rtc::ByteBufferWriter* buf) const override;
 
  private:
   std::vector<uint16_t>* attr_types_;
@@ -524,19 +508,8 @@
 // A "GTURN" STUN message.
 class RelayMessage : public StunMessage {
  protected:
-  virtual StunAttributeValueType GetAttributeValueType(int type) const {
-    switch (type) {
-      case STUN_ATTR_LIFETIME:            return STUN_VALUE_UINT32;
-      case STUN_ATTR_MAGIC_COOKIE:        return STUN_VALUE_BYTE_STRING;
-      case STUN_ATTR_BANDWIDTH:           return STUN_VALUE_UINT32;
-      case STUN_ATTR_DESTINATION_ADDRESS: return STUN_VALUE_ADDRESS;
-      case STUN_ATTR_SOURCE_ADDRESS2:     return STUN_VALUE_ADDRESS;
-      case STUN_ATTR_DATA:                return STUN_VALUE_BYTE_STRING;
-      case STUN_ATTR_OPTIONS:             return STUN_VALUE_UINT32;
-      default: return StunMessage::GetAttributeValueType(type);
-    }
-  }
-  virtual StunMessage* CreateNew() const { return new RelayMessage(); }
+  StunAttributeValueType GetAttributeValueType(int type) const override;
+  StunMessage* CreateNew() const override;
 };
 
 // Defined in TURN RFC 5766.
@@ -586,21 +559,8 @@
 extern const char STUN_ERROR_REASON_UNSUPPORTED_PROTOCOL[];
 class TurnMessage : public StunMessage {
  protected:
-  virtual StunAttributeValueType GetAttributeValueType(int type) const {
-    switch (type) {
-      case STUN_ATTR_CHANNEL_NUMBER:      return STUN_VALUE_UINT32;
-      case STUN_ATTR_TURN_LIFETIME:       return STUN_VALUE_UINT32;
-      case STUN_ATTR_XOR_PEER_ADDRESS:    return STUN_VALUE_XOR_ADDRESS;
-      case STUN_ATTR_DATA:                return STUN_VALUE_BYTE_STRING;
-      case STUN_ATTR_XOR_RELAYED_ADDRESS: return STUN_VALUE_XOR_ADDRESS;
-      case STUN_ATTR_EVEN_PORT:           return STUN_VALUE_BYTE_STRING;
-      case STUN_ATTR_REQUESTED_TRANSPORT: return STUN_VALUE_UINT32;
-      case STUN_ATTR_DONT_FRAGMENT:       return STUN_VALUE_BYTE_STRING;
-      case STUN_ATTR_RESERVATION_TOKEN:   return STUN_VALUE_BYTE_STRING;
-      default: return StunMessage::GetAttributeValueType(type);
-    }
-  }
-  virtual StunMessage* CreateNew() const { return new TurnMessage(); }
+  StunAttributeValueType GetAttributeValueType(int type) const override;
+  StunMessage* CreateNew() const override;
 };
 
 // RFC 5245 ICE STUN attributes.
@@ -624,19 +584,8 @@
 // A RFC 5245 ICE STUN message.
 class IceMessage : public StunMessage {
  protected:
-  virtual StunAttributeValueType GetAttributeValueType(int type) const {
-    switch (type) {
-      case STUN_ATTR_PRIORITY:
-      case STUN_ATTR_NETWORK_INFO:
-      case STUN_ATTR_NOMINATION:
-        return STUN_VALUE_UINT32;
-      case STUN_ATTR_USE_CANDIDATE:   return STUN_VALUE_BYTE_STRING;
-      case STUN_ATTR_ICE_CONTROLLED:  return STUN_VALUE_UINT64;
-      case STUN_ATTR_ICE_CONTROLLING: return STUN_VALUE_UINT64;
-      default: return StunMessage::GetAttributeValueType(type);
-    }
-  }
-  virtual StunMessage* CreateNew() const { return new IceMessage(); }
+  StunAttributeValueType GetAttributeValueType(int type) const override;
+  StunMessage* CreateNew() const override;
 };
 
 }  // namespace cricket