user32: Handle the undocumented behaviour in DefWindowProc for WM_NCACTIVATE…

dlls/user32/controls.h

@@ -90,7 +90,7 @@ extern UINT MENU_FindSubMenu( HMENU *hmenu, HMENU hSubTarget ) DECLSPEC_HIDDEN;
 
 /* nonclient area */
 extern LRESULT NC_HandleNCPaint( HWND hwnd , HRGN clip) DECLSPEC_HIDDEN;
-extern LRESULT NC_HandleNCActivate( HWND hwnd, WPARAM wParam ) DECLSPEC_HIDDEN;
+extern LRESULT NC_HandleNCActivate( HWND hwnd, WPARAM wParam, LPARAM lParam ) DECLSPEC_HIDDEN;
 extern LRESULT NC_HandleNCCalcSize( HWND hwnd, RECT *winRect ) DECLSPEC_HIDDEN;
 extern LRESULT NC_HandleNCHitTest( HWND hwnd, POINT pt ) DECLSPEC_HIDDEN;
 extern LRESULT NC_HandleNCLButtonDown( HWND hwnd, WPARAM wParam, LPARAM lParam ) DECLSPEC_HIDDEN;

dlls/user32/defwnd.c

@@ -386,7 +386,7 @@ static LRESULT DEFWND_DefWinProc( HWND hwnd, UINT msg, WPARAM wParam, LPARAM lPa
         break;
 
     case WM_NCACTIVATE:
-        return NC_HandleNCActivate( hwnd, wParam );
+        return NC_HandleNCActivate( hwnd, wParam, lParam );
 
     case WM_NCDESTROY:
         {

dlls/user32/nonclient.c

@@ -1123,7 +1123,7 @@ LRESULT NC_HandleNCPaint( HWND hwnd , HRGN clip)
  *
  * Handle a WM_NCACTIVATE message. Called from DefWindowProc().
  */
-LRESULT NC_HandleNCActivate( HWND hwnd, WPARAM wParam )
+LRESULT NC_HandleNCActivate( HWND hwnd, WPARAM wParam, LPARAM lParam )
 {
     WND* wndPtr = WIN_GetPtr( hwnd );
 
@@ -1138,10 +1138,16 @@ LRESULT NC_HandleNCActivate( HWND hwnd, WPARAM wParam )
     else wndPtr->flags &= ~WIN_NCACTIVATED;
     WIN_ReleasePtr( wndPtr );
 
-    if (IsIconic(hwnd))
-        WINPOS_RedrawIconTitle( hwnd );
-    else
-        NC_DoNCPaint( hwnd, (HRGN)1, FALSE );
+    /* This isn't documented but is reproducible in at least XP SP2 and
+     * Outlook 2007 depends on it
+     */
+    if (lParam != -1)
+    {
+        if (IsIconic(hwnd))
+            WINPOS_RedrawIconTitle( hwnd );
+        else
+            NC_DoNCPaint( hwnd, (HRGN)1, FALSE );
+    }
 
     return TRUE;
 }