oleaut32/tests: Fix the IPicture::Render() usage.

oleaut32/tests: Fix the IPicture::Render() usage.

When one specifies the target rectangle (0, 0, width, -height)
IPicture::Render() places the origin at 0,0 and flips the image
vertically. This means that in order to paint an icon on the DC
it's necessary to specify the rectangle (0, height, width, -height),
i.e. place the origin at 0,height. I've written a test app that
verifies this behaviour, ufortunately I don't see a way to add
a Wine test case for this.

The test currently works by chance under Windows because in case
of (0, 0, width, -height) IPicture::Render() draws black rectangle
instead of an icon at (0, 0, width, height). If Wine intends to
replicate this behaviour it should be fixed by a separate patch.

Signed-off-by: Dmitry Timoshkov <dmitry@baikal.ru>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>