After introducing column-span, the ColumnSetWrapperFrame can have more
than one ColumnSetFrame children if there's any column-span:all child.
Thus we cannot use "height:100%" to pass block size information down to
the -moz-column-content's children.
Skip column span wrapper in nsIFrame::IsBlockWrapper() so that the
percentage column-span:all works.
Before this patch, the height of column contents are set to 100% of the
multicol container, so if the previous in-flows of column content
anonymous boxes consume all the height, later in-flows's height are all
0. In this patch, we don't restrict column-content's height, so their
height are calculated based on their children's height.
column-contain-1a.html passes because it can now correctly calculate the
union of all the column content's rect to find the correct sticky
positioning.
Differential Revision: https://phabricator.services.mozilla.com/D27627
--HG--
extra : moz-landing-system : lando