tree 68452879304184007386978537ac60f4fb01a20e
parent b318a28f33bd062c2dc4759fd54bed5188a88e49
author Xianzhu Wang <wangxianzhu@chromium.org> 1700419582 +0000
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1700419582 +0000

[IntersectionOptimization] Accumulate scroll delta per IntersectionObservation

UMA metrics added in crrev.com/1193840 show that most
IntersectionObservations have big min_scroll_delta_to_update, but
most LocalFrameViews have very small min_scroll_delta_to_update. This
means that a few IntersectionObservations with small
min_scroll_delta_to_update cause the optimization not effective.

Now track accumulated scroll delta per IntersectionObservation so that
we can still skip update for a IntersectionObservation with a big
min_scroll_delta_to_update despite other IntersectionObservations with
small min_scroll_delta_to_update.

Bug: 1400495
Change-Id: I69ec0f80248a9fb8b1120d2d84df703c5e6f6597
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4906672
Reviewed-by: Stefan Zager <szager@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1226578}