The longest frame the warp rate is honored across, in wall-clock seconds.
Past this a frame is a stall — a backgrounded tab, a shader compile — not a
slow frame, and buying 1,920× of it would be the spiral of death with extra
steps. 100 ms keeps the rate honest down to 10 fps, which is below any frame
rate worth warping at, and caps a stalled frame's catch-up at
MAX_WARP_STEPS ticks (~10 ms of work at the rate measured above).