replace NULL->nullptr in src/remoting.

remoting/host/setup/daemon_installer_win.h

Index: remoting/host/setup/daemon_installer_win.h
diff --git a/remoting/host/setup/daemon_installer_win.h b/remoting/host/setup/daemon_installer_win.h
index 3709982a97013dc457ce15bfe4bce19dcc5f6686..7aaa2eb7e2aab84ab251a8da9edd87d69ca39c27 100644
--- a/remoting/host/setup/daemon_installer_win.h
+++ b/remoting/host/setup/daemon_installer_win.h
@@ -24,7 +24,7 @@ class DaemonInstallerWin {
 
   // Creates an instance of the Chromoting Host installer passing the completion
   // callback to be called when the installation finishes. In case of an error
-  // returns NULL and passed the error code to |done|.
+  // returns nullptr and passed the error code to |done|.
   static scoped_ptr<DaemonInstallerWin> Create(HWND window_handle,
                                                CompletionCallback done);
 
@@ -44,7 +44,7 @@ class DaemonInstallerWin {
 
 // Returns the first top-level (i.e. WS_OVERLAPPED or WS_POPUP) window in
 // the chain of parents of |window|. Returns |window| if it represents
-// a top-level window. Returns NULL when |window| is NULL.
+// a top-level window. Returns nullptr when |window| is nullptr.
 HWND GetTopLevelWindow(HWND window);
 
 }  // namespace remoting