This is an issue because a driver may have to maintain two copies of a
texture if it batches all uploads together at the start of a frame.
In the Vulkan backend, we do something similar to avoid breaking out of a
render pass to copy a texture from the streaming buffer to the destination
image.
This was causing issues in the sms-bubbles fifolog, where an EFB copy to
the same address of a previously-used texture caused the previous texture
to be re-used again for a different image later on in the frame, causing
the original contents to be discarded.
Stenzek
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