Replace NULL with nullptr in all C++ files.

webrtc/modules/desktop_capture/x11/shared_x_display.cc

 /*
  *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 15 matching lines @@
 
 SharedXDisplay::~SharedXDisplay() {
   RTC_DCHECK(event_handlers_.empty());
   XCloseDisplay(display_);
 }
 
 // static
 rtc::scoped_refptr<SharedXDisplay> SharedXDisplay::Create(
     const std::string& display_name) {
   Display* display =
-      XOpenDisplay(display_name.empty() ? NULL : display_name.c_str());
+      XOpenDisplay(display_name.empty() ? nullptr : display_name.c_str());
   if (!display) {
     LOG(LS_ERROR) << "Unable to open display";
-    return NULL;
+    return nullptr;
   }
   return new SharedXDisplay(display);
 }
 
 // static
 rtc::scoped_refptr<SharedXDisplay> SharedXDisplay::CreateDefault() {
   return Create(std::string());
 }
 
 void SharedXDisplay::AddEventHandler(int type, XEventHandler* handler) {
@@ skipping 31 matching lines @@
       continue;
     for (std::vector<XEventHandler*>::iterator it = handlers->second.begin();
          it != handlers->second.end(); ++it) {
       if ((*it)->HandleXEvent(e))
         break;
     }
   }
 }
 
 }  // namespace webrtc