[PATCH 1/3] windowscodecs: Add initial implementation of the GIF encoder.

[Esme Povirk (they/them)]

+        if (hr == S_OK)
+            hr = write_source(iface, source, rc, format, 8, FALSE,
This->width, This->height);

I think needs_palette should probably be something like !This->colors.

+        if (state->user_write_data(state->user_ptr, &byte, 1) != 1)
+            return 0;

Why do we use this kind of abstraction for an internal function? Was
this imported from another project?

If possible, I would prefer not to maintain an implementation of LZW
compression.