Add better support for lots of thin ticks by:

  * Removing stroke on ticks (so that the stroke isn't thicker than the
    tick itself)
  * Alternating colours of the ticks between light and dark (so that
    neighbouring ticks are still distinguishable)
  * Making selection drawing use isInputPending to allow faster looping
    over multiple ticks.

Change-Id: Iaa13fe4820d3d3168e085dfc01d7581cbc1739f0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2959626
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75146}