[Gecko Bug 2055303] Reparent abspos children in non-first inline continuation in a fragmentainer during column balancing.#61533
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…ntainer during column balancing. This patch adds a new sanity check in absolute containing block for inline as abspos containing block. It ensures only the first inline continuation in a fragmentainer can contain abspos children, and all the other continuations in the same fragmentainer cannot. The crashtest added in this patch can trigger the assertions without the fix in `PrepareAbsoluteFrames()`. The fix in `PrepareAbsoluteFrames()` has two parts: the first part after `DrainPushedChildList()` is to ensure the above-mentioned invariant that the new check verifies. The second part is to generalize existing logic, ensuring at most one continuation of an abspos frame can be in the child list. The check for this is at [1]. [1] https://searchfox.org/firefox-main/rev/3b3f727963c10fe58e6e72c15989ad0e35dbf832/layout/generic/AbsoluteContainingBlock.cpp#344-351 Differential Revision: https://phabricator.services.mozilla.com/D313899 bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=2055303 gecko-commit: ac9d3ffd60fc50cf8497e130e256723ec98c1ce8 gecko-reviewers: layout-reviewers, dshin
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This patch adds a new sanity check in absolute containing block for inline as
abspos containing block. It ensures only the first inline continuation in a
fragmentainer can contain abspos children, and all the other continuations in
the same fragmentainer cannot. The crashtest added in this patch can trigger the
assertions without the fix in
PrepareAbsoluteFrames().The fix in
PrepareAbsoluteFrames()has two parts: the first part afterDrainPushedChildList()is to ensure the above-mentioned invariant that the newcheck verifies. The second part is to generalize existing logic, ensuring at
most one continuation of an abspos frame can be in the child list. The check for
this is at [1].
[1] https://searchfox.org/firefox-main/rev/3b3f727963c10fe58e6e72c15989ad0e35dbf832/layout/generic/AbsoluteContainingBlock.cpp#344-351
Differential Revision: https://phabricator.services.mozilla.com/D313899
bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=2055303
gecko-commit: ac9d3ffd60fc50cf8497e130e256723ec98c1ce8
gecko-reviewers: layout-reviewers, dshin