wined3d: Don't clear the GL context if it's not the one being destroyed by context_destroy_gl_resources().

The previous code clears the GL context if the context being destroyed is
not valid, even though the current one is some arbitrary, unrelated context.

Also rename to sfnt2fon to better reflect usage and avoid conflicts
with the previous binary on updates.

msxml3: Use interface instead of implementation pointer to forward IEnumVARIANT::AddRef and IEnumVARIANT::Release for IXMLElementCollection.

msxml3: Add separate QueryInterface implementation for IEnumVARIANT interface exported by IXMLElementCollection.

msxml3/tests: Add a test to show that IXMLElementCollection enumerator doesn't recognize IID_IXMLElementCollection.