[3/3] windowscodecs: Implement GetThumbnail in the PNG frame decoder.

[Dmitry Timoshkov]

---
 dlls/windowscodecs/pngformat.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/dlls/windowscodecs/pngformat.c b/dlls/windowscodecs/pngformat.c
index fb45804..4183d8e 100644
--- a/dlls/windowscodecs/pngformat.c
+++ b/dlls/windowscodecs/pngformat.c
@@ -903,8 +903,12 @@ static HRESULT WINAPI PngDecoder_Frame_GetColorContexts(IWICBitmapFrameDecode *i
 static HRESULT WINAPI PngDecoder_Frame_GetThumbnail(IWICBitmapFrameDecode *iface,
     IWICBitmapSource **ppIThumbnail)
 {
-    FIXME("(%p,%p): stub\n", iface, ppIThumbnail);
-    return E_NOTIMPL;
+    TRACE("(%p,%p)\n", iface, ppIThumbnail);
+
+    if (!ppIThumbnail) return E_INVALIDARG;
+
+    *ppIThumbnail = NULL;
+    return WINCODEC_ERR_CODECNOTHUMBNAIL;
 }
 
 static const IWICBitmapFrameDecodeVtbl PngDecoder_FrameVtbl = {
-- 
1.8.0.1