Check popover_ in IsAppearanceBasePicker()
Currently, if either the size or multiple attribute is changed,
ChangeRendering() -> UpdateMutationObserver() ->
IsAppearanceBasePicker() are called before
MenuListSelectType::CreateShadowSubtree(), which initializes
popover_. As a result, we are accessing a null object in
IsAppearanceBasePicker() when trying to get its computed style. This CL checks for popover_ and select_ before trying to get their computed style and adds two tests to validate behavior (added linux_chromium_asan_rel_ng tryjob).
Bug: 377966015
Change-Id: Id5032fdcc4d51e78e848f7e6c5ce8357ca0def02
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6013239
Reviewed-by: Joey Arhar jarhar@chromium.org
Commit-Queue: Ana Sollano Kim ansollan@microsoft.com
Cr-Commit-Position: refs/heads/main@{#1383323}