OOBE: Fix high CPU usage on login screen

The login page is a part of the OOBE screens. This means all of the OOBE
screens are loaded when the login page is presented, but they are all
marked hidden to not be visible to the user. Because everything is
loaded, the lottie animations used for the fingerprint setup is also
loaded and autoplayed. This resulted in a high CPU usage of ~30% on the
login screen (nocturne).

This patch removes the autoplay of the fingerprint setup animation and
instead only plays it when the screen is made visible. To achieve this,
the patch also adds supports for pausing and playing to the lottie
player in third_party.

Original Bug: 998991
Change-Id: I20700c9d807fc0dd4c08c1f2da66019881b15160
Tested: Manually for correctness and CPU usage. Also updated unit test
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1777086
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Commit-Queue: Malay Keshav <malaykeshav@chromium.org>
Cr-Commit-Position: refs/heads/master@{#696948}
(cherry picked from commit 05fab25ab1b63f962b3e53027e5ad4edf0d908fb)

TBR=stevenjb,oshima

Bug: 1017588
Change-Id: I20700c9d807fc0dd4c08c1f2da66019881b15160
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1907070
Reviewed-by: Malay Keshav <malaykeshav@chromium.org>
Cr-Commit-Position: refs/branch-heads/3904@{#868}
Cr-Branched-From: 675968a8c657a3bd9c1c2c20c5d2935577bbc5e6-refs/heads/master@{#693954}
8 files changed