wined3d: Avoid a NULL dereference in RealizePalette.

dlls/wined3d/surface.c

@@ -1773,14 +1773,24 @@ HRESULT WINAPI IWineD3DSurfaceImpl_RealizePalette(IWineD3DSurface *iface) {
         This->Flags |= SFLAG_DIRTY;
     }
 
-    TRACE("(%p): Updating the palette\n", This);
-    for (n=0; n<256; n++) {
-        col[n].rgbRed   = pal->palents[n].peRed;
-        col[n].rgbGreen = pal->palents[n].peGreen;
-        col[n].rgbBlue  = pal->palents[n].peBlue;
-        col[n].rgbReserved = 0;
+    if(This->Flags & SFLAG_DIBSECTION) {
+        TRACE("(%p): Updating the hdc's palette\n", This);
+        for (n=0; n<256; n++) {
+            if(pal) {
+                col[n].rgbRed   = pal->palents[n].peRed;
+                col[n].rgbGreen = pal->palents[n].peGreen;
+                col[n].rgbBlue  = pal->palents[n].peBlue;
+            } else {
+                IWineD3DDeviceImpl *device = This->resource.wineD3DDevice;
+                /* Use the default device palette */
+                col[n].rgbRed   = device->palettes[device->currentPalette][n].peRed;
+                col[n].rgbGreen = device->palettes[device->currentPalette][n].peGreen;
+                col[n].rgbBlue  = device->palettes[device->currentPalette][n].peBlue;
+            }
+            col[n].rgbReserved = 0;
+        }
+        SetDIBColorTable(This->hDC, 0, 256, col);
     }
-    SetDIBColorTable(This->hDC, 0, 256, col);
 
     return WINED3D_OK;
 }