Findit identified the culprit r574755 with confidence 70.0% in the config "chromium.linux / Linux Tests"
based on the flakiness trend:

https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVyxQELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCKOAWNocm9taXVtLmxpbnV4L0xpbnV4IFRlc3RzLzcxMDA4L2NvbnRlbnRfYnJvd3NlcnRlc3RzL1UybDBaVkJsY2xCeWIyTmxjM05DY205M2MyVnlWR1Z6ZEM1RGFHbHNaRVp5WVcxbFEzSmhjMmhOWlhSeWFXTnpYMU5qY205c2JHVmtTVzUwYjFacFpYYz0MCxITTWFzdGVyRmxha2VBbmFseXNpcxgBDA

If the culprit above is wrong, please file a bug using this link and hit submit:
https://bugs.chromium.org/p/chromium/issues/entry?status=Unconfirmed&labels=Pri-1,Test-Findit-Wrong&components=Tools%3ETest%3EFindit%3EFlakiness&summary=%5BFindit%5D%20Flake%20Analyzer%20-%20Wrong%20result%20for%20SitePerProcessBrowserTest.ChildFrameCrashMetrics_ScrolledIntoView&comment=Link%20to%20Analysis%3A%20https://findit-for-me.appspot.com/waterfall/flake?key=ag9zfmZpbmRpdC1mb3ItbWVyxQELEhdNYXN0ZXJGbGFrZUFuYWx5c2lzUm9vdCKOAWNocm9taXVtLmxpbnV4L0xpbnV4IFRlc3RzLzcxMDA4L2NvbnRlbnRfYnJvd3NlcnRlc3RzL1UybDBaVkJsY2xCeWIyTmxjM05DY205M2MyVnlWR1Z6ZEM1RGFHbHNaRVp5WVcxbFEzSmhjMmhOWlhSeWFXTnpYMU5qY205c2JHVmtTVzUwYjFacFpYYz0MCxITTWFzdGVyRmxha2VBbmFseXNpcxgBDA

Automatically posted by the findit-for-me app (https://goo.gl/Ot9f7N).

Trying a revert of r574755

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/31d871700a2c92f0c03023f10c8b77b08694e487

commit 31d871700a2c92f0c03023f10c8b77b08694e487
Author: Xiaocheng Hu <xiaochengh@chromium.org>
Date: Mon Jul 16 23:16:59 2018

Revert "[IO] Only compute intersection observations if any property tree state has changed, and only for full-frame updates."

This reverts commit cdea59c0db145f8e85ea00e9f6d31642929e2397.

Reason for revert: Suspect of causing flakes in SitePerProcessBrowserTest.ChildFrameCrashMetrics_ScrolledIntoView

Original change's description:
> [IO] Only compute intersection observations if any property tree state has changed, and only for full-frame updates.
> 
> This avoids re-computing intersection observations when nothing has changed.
> 
> It is correct for IOv1 and also IOv2. It is correct for IOv2 because at present
> IOv2 and hit testing do not depend on paint output.
> 
> Bug:  831762 
> Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
> Change-Id: I196ca3a64e26d2227bc8cbb6b73ea81c1adbb4b2
> Reviewed-on: https://chromium-review.googlesource.com/1134348
> Reviewed-by: Stefan Zager <szager@chromium.org>
> Reviewed-by: vmpstr <vmpstr@chromium.org>
> Commit-Queue: Chris Harrelson <chrishtr@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#574755}

TBR=szager@chromium.org,vmpstr@chromium.org,chrishtr@chromium.org

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug:  831762 ,  863946 
Change-Id: I30ab56ebce4cb3e677623f7663eb2795b0201274
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Reviewed-on: https://chromium-review.googlesource.com/1138894
Reviewed-by: Xiaocheng Hu <xiaochengh@chromium.org>
Commit-Queue: Xiaocheng Hu <xiaochengh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#575473}
[modify] https://crrev.com/31d871700a2c92f0c03023f10c8b77b08694e487/third_party/blink/renderer/core/frame/frame_view.h
[modify] https://crrev.com/31d871700a2c92f0c03023f10c8b77b08694e487/third_party/blink/renderer/core/frame/local_frame_view.cc
[modify] https://crrev.com/31d871700a2c92f0c03023f10c8b77b08694e487/third_party/blink/renderer/core/frame/local_frame_view.h
[modify] https://crrev.com/31d871700a2c92f0c03023f10c8b77b08694e487/third_party/blink/renderer/core/frame/remote_frame_view.cc
[modify] https://crrev.com/31d871700a2c92f0c03023f10c8b77b08694e487/third_party/blink/renderer/core/frame/remote_frame_view.h
[modify] https://crrev.com/31d871700a2c92f0c03023f10c8b77b08694e487/third_party/blink/renderer/core/scheduler/frame_throttling_test.cc