DOM: Capture apparent getSelection() getter side effects
This CL adds tests (and unfortunately, expectations) for a bug that has
to do with getters on getSelection() having side effects on the
internal range maintained by blink::DOMSelection, when a selection's
anchor node is removed from the DOM.
R=masonf
Bug: 379275917
Change-Id: Ic69f910b5d070a55a6f0c3992f45c0ad939124d0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6026810
Reviewed-by: Mason Freed masonf@chromium.org
Commit-Queue: Dominic Farolino dom@chromium.org
Cr-Commit-Position: refs/heads/main@{#1384416}