Make columns work with line grids. They need to set up the line grid pagination origin properly, and regions/flow threads have a bug or two that needs to be fixed.
Created attachment 223752 [details] Patch
Comment on attachment 223752 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=223752&action=review > Source/WebCore/rendering/LayoutState.h:89 > + LayoutSize pageOffset() const { return m_pageOffset; } Is this really offsetFromPage()? that would be a clearer name than pageOffset (which could be the offset of a page).
(In reply to comment #2) > (From update of attachment 223752 [details]) > View in context: https://bugs.webkit.org/attachment.cgi?id=223752&action=review > > > Source/WebCore/rendering/LayoutState.h:89 > > + LayoutSize pageOffset() const { return m_pageOffset; } > > Is this really offsetFromPage()? that would be a clearer name than pageOffset (which could be the offset of a page). It's actually really complicated what that represents. It is the cumulative offset of the logical top of the first page within the layout state. I agree it needs a better name, but should probably be a separate patch, since it's a member variable and that term is used all over.
Comment on attachment 223752 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=223752&action=review > Source/WebCore/rendering/LayoutState.cpp:-227 > -void LayoutState::computeLineGridPaginationOrigin(RenderBox* renderer) Should remove the method declaration from the .h file too. > Source/WebCore/rendering/RenderBox.cpp:-4414 > - || isMultiColumnBlockFlow(); With this change, isMultiColumnBlockFlow() will become unused, won't it? Anyway, I wonder if you should keep it here, since paginating a multicol still doesn't work.
Landed in r163878