Replace NULL with nullptr in all C++ files.

webrtc/p2p/base/stunport_unittest.cc

Index: webrtc/p2p/base/stunport_unittest.cc
diff --git a/webrtc/p2p/base/stunport_unittest.cc b/webrtc/p2p/base/stunport_unittest.cc
index aa708c1ba196533a88d9b353e1f52671bfa8bada..f8d41bfbacb7cfe410882b4f69fc8f1abd30913a 100644
--- a/webrtc/p2p/base/stunport_unittest.cc
+++ b/webrtc/p2p/base/stunport_unittest.cc
@@ -91,14 +91,14 @@ class StunPortTestBase : public testing::Test, public sigslot::has_slots<> {
   void CreateSharedUdpPort(const rtc::SocketAddress& server_addr) {
     socket_.reset(socket_factory_.CreateUdpSocket(
         rtc::SocketAddress(kLocalAddr.ipaddr(), 0), 0, 0));
-    ASSERT_TRUE(socket_ != NULL);
+    ASSERT_TRUE(socket_ != nullptr);
     socket_->SignalReadPacket.connect(this, &StunPortTestBase::OnReadPacket);
     stun_port_.reset(cricket::UDPPort::Create(
         rtc::Thread::Current(), &socket_factory_,
         &network_, socket_.get(),
         rtc::CreateRandomString(16), rtc::CreateRandomString(22),
         std::string(), false));
-    ASSERT_TRUE(stun_port_ != NULL);
+    ASSERT_TRUE(stun_port_ != nullptr);
     ServerAddresses stun_servers;
     stun_servers.insert(server_addr);
     stun_port_->set_server_addresses(stun_servers);
@@ -127,8 +127,7 @@ class StunPortTestBase : public testing::Test, public sigslot::has_slots<> {
  protected:
   static void SetUpTestCase() {
     // Ensure the RNG is inited.
-    rtc::InitRandom(NULL, 0);
-
+    rtc::InitRandom(nullptr, 0);
   }
 
   void OnPortComplete(cricket::Port* port) {