chore: cherry-pick d74ba931c4b7 from chromium

[ppontes]

content-visibility: Don't adjust position of a locked hittest result node.

This patch ensures that if we have a hittest result that has a locked
node, we don't try to recurse into its subtree. This can happen when we
do a PositionWithAffinity check.

R=chrishtr@chromium.org

(cherry picked from commit 8483cf6944e38203c3b247163c54cfa105e89c56)

(cherry picked from commit 3f7b67374a1121b6756ccfd2e4e414987f167489)

Bug: 1162131
Change-Id: I357bd7032c6c2b6c9405bf26c49a36bda22d6a0d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2611453
Reviewed-by: Chris Harrelson chrishtr@chromium.org
Commit-Queue: vmpstr vmpstr@chromium.org
Cr-Original-Original-Commit-Position: refs/heads/master@{#840727}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2618603
Reviewed-by: Xianzhu Wang wangxianzhu@chromium.org
Reviewed-by: Krishna Govind govind@chromium.org
Cr-Original-Commit-Position: refs/branch-heads/4324@{#1566}
Cr-Original-Branched-From: c73b5a651d37a6c4d0b8e3262cc4015a5579c6c8-refs/heads/master@{#827102}
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2618982
Commit-Queue: Achuith Bhandarkar achuith@chromium.org
Reviewed-by: Victor-Gabriel Savu vsavu@google.com
Cr-Commit-Position: refs/branch-heads/4240@{#1520}
Cr-Branched-From: f297677702651916bbf65e59c0d4bbd4ce57d1ee-refs/heads/master@{#800218}

Notes: Security: backported fix for CVE-2021-21122.

[release-clerk]

Release Notes Persisted

Security: backported fix for CVE-2021-21122.