dwmapi: Add stub for DwmDefWindowProc.

dlls/dwmapi/dwmapi.spec

@@ -21,7 +21,7 @@
 120 stub @
 
 @ stub DwmAttachMilContent
-@ stub DwmDefWindowProc
+@ stdcall DwmDefWindowProc(long long long long ptr)
 @ stub DwmDetachMilContent
 @ stdcall DwmEnableBlurBehindWindow(ptr ptr)
 @ stdcall DwmEnableMMCSS(long)

dlls/dwmapi/dwmapi_main.c

@@ -176,3 +176,15 @@ HRESULT WINAPI DwmEnableBlurBehindWindow(HWND hWnd, const DWM_BLURBEHIND *pBlurB
 
     return E_NOTIMPL;
 }
+
+/**********************************************************************
+ *           DwmDefWindowProc         (DWMAPI.@)
+ */
+BOOL WINAPI DwmDefWindowProc(HWND hWnd, UINT Msg, WPARAM wParam, LPARAM lParam, LRESULT *plResult)
+{
+    static int i;
+
+    if (!i++) FIXME("stub\n");
+
+    return FALSE;
+}

include/dwmapi.h

@@ -53,6 +53,7 @@ typedef struct _DWM_BLURBEHIND
     BOOL fTransitionOnMaximized;
 } DWM_BLURBEHIND, *PDWM_BLURBEHIND;
 
+DWMAPI DwmDefWindowProc(HWND, UINT, WPARAM, LPARAM, LRESULT*);
 DWMAPI DwmEnableBlurBehindWindow(HWND, const DWM_BLURBEHIND *);
 DWMAPI DwmEnableComposition(UINT);
 DWMAPI DwmEnableMMCSS(BOOL);