Run clang-modernize -use-nullptr over src/extensions/.

extensions/browser/api/socket/socket.cc

Index: extensions/browser/api/socket/socket.cc
diff --git a/extensions/browser/api/socket/socket.cc b/extensions/browser/api/socket/socket.cc
index afec38f46df44c8c79b5cd82f1d12f9a561fdfe4..a9ee15ef00596a5a8112b0409a884b094c81af28 100644
--- a/extensions/browser/api/socket/socket.cc
+++ b/extensions/browser/api/socket/socket.cc
@@ -64,7 +64,7 @@ void Socket::WriteData() {
 }
 
 void Socket::OnWriteComplete(int result) {
-  io_buffer_write_ = NULL;
+  io_buffer_write_ = nullptr;
 
   WriteRequest& request = write_queue_.front();
 
@@ -98,7 +98,7 @@ int Socket::Listen(const std::string& address,
 }
 
 void Socket::Accept(const AcceptCompletionCallback& callback) {
-  callback.Run(net::ERR_FAILED, NULL);
+  callback.Run(net::ERR_FAILED, nullptr);
 }
 
 // static