Normally, the total and skipped frame count for the encoder is performed
in the video-io thread. However, because a new thread is being
introduced for texture-based encoding, the frontend has no way of being
able to query that. So, instead of making the frontend query that data
separately, just make the texture encoder thread increment the values of
video-io. That way, the frontend doesn't need to change any code, and
can continue using the same functions for determining the total/skipped
frame count.
This can cause the frame count to be doubled if both a texture-based
encoder and a raw data encoder is active at the same time, but it's an
acceptable alternative.