In particular: in our frontend code, if we happen to end up with a flex/grid
item with 'display:-moz-box', we want it to take the same sizing codepath as
other flex/grid items, which are all block-level (even though -moz-box is not
exactly block-level itself). Notably, we want to use ComputeSizeFlags::eDefault
for sizing (like we do for real block-level things), because that's necessary
in order for grid items to stretch correctly in their inline axis.
Also: this patch renames "isBlock" to "isBlockLevel" to reflect reality. Its
naming is based on the constant NS_CSS_FRAME_TYPE_BLOCK, which in fact is not
specific to 'display:block' but in fact is for frames that are "block-level in
normal flow" (which I think in practice means block-level and not
out-of-flow). That is documented here:
https://searchfox.org/mozilla-central/rev/7531325c8660cfa61bf71725f83501028178cbb9/layout/generic/ReflowInput.h#51
Differential Revision: https://phabricator.services.mozilla.com/D46539
--HG--
extra : moz-landing-system : lando