The regressing bug stopped passing the perspective flag to GetResultingTransformMatrixInternal if we know the frame did not have perspective in order to save time. But it missed that we pass the flags up in a recursive call if the frame has preserve3d. In all cases where we pass the preserve3d flag we also want to include perspective (if it exists), so it is fine to just always pass the perspective flag in these preserve3d recursive calls. It does not cause wasted effort because we have to check perspective at least once and we will only check it once.
Original Revision: https://phabricator.services.mozilla.com/D227294
Differential Revision: https://phabricator.services.mozilla.com/D227579
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