diff --git a/rtc_base/win32window.cc b/rtc_base/win32window.cc
index f55a8ba..9e9c839 100644
--- a/rtc_base/win32window.cc
+++ b/rtc_base/win32window.cc
@@ -87,10 +87,20 @@
   return false;
 }
 
-LRESULT Win32Window::WndProc(HWND hwnd, UINT uMsg,
-                             WPARAM wParam, LPARAM lParam) {
-  Win32Window* that = reinterpret_cast<Win32Window*>(
-      ::GetWindowLongPtr(hwnd, GWLP_USERDATA));
+bool Win32Window::OnClose() {
+  return true;
+}
+
+void Win32Window::OnNcDestroy() {
+  // Do nothing. }
+}
+
+LRESULT Win32Window::WndProc(HWND hwnd,
+                             UINT uMsg,
+                             WPARAM wParam,
+                             LPARAM lParam) {
+  Win32Window* that =
+      reinterpret_cast<Win32Window*>(::GetWindowLongPtr(hwnd, GWLP_USERDATA));
   if (!that && (WM_CREATE == uMsg)) {
     CREATESTRUCT* cs = reinterpret_cast<CREATESTRUCT*>(lParam);
     that = static_cast<Win32Window*>(cs->lpCreateParams);