Replace NULL with nullptr in all C++ files.

webrtc/examples/peerconnection/client/main.cc

Index: webrtc/examples/peerconnection/client/main.cc
diff --git a/webrtc/examples/peerconnection/client/main.cc b/webrtc/examples/peerconnection/client/main.cc
index 413069d5e90c35fc3aaa5b42343efc8f4b46a937..a65cbf78788a42be854b06cd072ffd8a78262de2 100644
--- a/webrtc/examples/peerconnection/client/main.cc
+++ b/webrtc/examples/peerconnection/client/main.cc
@@ -30,7 +30,7 @@ int PASCAL wWinMain(HINSTANCE instance, HINSTANCE prev_instance,
 
   rtc::FlagList::SetFlagsFromCommandLine(&argc, argv, true);
   if (FLAG_help) {
-    rtc::FlagList::Print(NULL, false);
+    rtc::FlagList::Print(nullptr, false);
     return 0;
   }
 
@@ -55,7 +55,7 @@ int PASCAL wWinMain(HINSTANCE instance, HINSTANCE prev_instance,
   // Main loop.
   MSG msg;
   BOOL gm;
-  while ((gm = ::GetMessage(&msg, NULL, 0, 0)) != 0 && gm != -1) {
+  while ((gm = ::GetMessage(&msg, nullptr, 0, 0)) != 0 && gm != -1) {
     if (!wnd.PreTranslateMessage(&msg)) {
       ::TranslateMessage(&msg);
       ::DispatchMessage(&msg);
@@ -64,7 +64,7 @@ int PASCAL wWinMain(HINSTANCE instance, HINSTANCE prev_instance,
 
   if (conductor->connection_active() || client.is_connected()) {
     while ((conductor->connection_active() || client.is_connected()) &&
-           (gm = ::GetMessage(&msg, NULL, 0, 0)) != 0 && gm != -1) {
+           (gm = ::GetMessage(&msg, nullptr, 0, 0)) != 0 && gm != -1) {
       if (!wnd.PreTranslateMessage(&msg)) {
         ::TranslateMessage(&msg);
         ::DispatchMessage(&msg);