Unify the QueryInterface implementation a bit with the rest of wined3d while
we're at it.

Found by Valgrind.

In simple mode, StreamWriteAt would assume that StreamSetSize uses the size
it asks for, but in some cases the size would be pushed above the small block
limit. StreamWriteAt would then attempt to write using a small block chain,
even though a big block chain was created.

crypt32: Don't get confused matching URLs with a colon in the userinfo portion (e.g. user:password@domain).