Caused by rB85fe12071ad7.
When looking at a render pass in viewport and move the camera, there's a
"flash" effect in this AOVs test file:
{F9753476}
{F9753473}
The cause seems to be that taa_current_sample when rendering
(DRW_state_is_image_render()) is ok because it has been incremented in
EEVEE_temporal_sampling_draw but taa_current_sample is wrong when we are
not rendering.
D10375 by Ulysse Martin (youle) with clang format changes.
Reviewed By: jbakker, lichtwerk, also blessing from fclem
Differential Revision: https://developer.blender.org/D10375
75580fa6a6