Let LayoutObject::InvalidateIntersectionObserverCachedRects() schedule update

Previously all callers of
LayoutObject::InvalidateIntersectionObserverCachedRects() called
LocalFrameView::SetIntersectionObservationState() immediately.
Now let the former call the latter to ensure intersection observation
update will be always scheduled when any cached rects are invalidated.

This is a pure refactor without any behavior change.

Bug: 1400495
Change-Id: I79dbee97c9f49c055624d2c567e145ded8bd0d31
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4909747
Reviewed-by: Stefan Zager <szager@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1204951}