When an async video source is about to be rendered, the async texture
should be updated before any effect filtering occurs, rather than right
when it's about to render.
Fixes a few bugs:
- If the async texture hadn't drawn for its first time, and the source
has an effect filter, it would never end up rendering the first
frame due to the fact that it would fail on obs-source.c:2434 for the
first filter, causing it to never actually render the source, and thus
never get to a point in which it could call set_async_texture_size to
establish the async texture width/height for the first time.
- Any time the async texture size changed, it would only update the
async texture size at the end of the filter loop, which means that the
first frame after a size change would use the old size for the filters
rather than update to the new size right away.
fea4f75157