tdf#134298 sw: layout: remove left-over page frame without content

Once tdf#138039 is fixed, this bugdoc has an additional empty page 3.

This is because it first goes to 3 pages, and then the SwTextFrame
on page does a MoveBwd, leaving behind a page frame with just a body
frame and nothing else.

It turns out that SwRootFrame::RemoveSuperfluous() only removes
empty frames at the end of the document, but here there's a non-empty
frame following it.  Also, this function doesn't handle cases like
right/left page styles so it can't delete pages in the middle.

SwFrame::CheckPageDescs() doesn't remove page frames that don't have
content, it only removes those that have the intentionally-empty flag set.

Extend CheckPageDescs() to also remove page frames that don't have
content, and make sure it is called when SwContentFrame::Cut()
removes the last content from a page frame (it will be called after
all pages are valid in SwLayAction::InternalAction()).

(Alternatively it might be possible to prevent the problem from
occurring in SwTextFly::ForEach() by ignoring the fly so that the first
paragraph never leaves page 1, but we didn't explore that.)

Reviewed-on: https://gerrit.libreoffice.org/c/core/+/105810
Tested-by: Jenkins
Reviewed-by: Michael Stahl <michael.stahl@cib.de>
(cherry picked from commit b9ef71476fd70bc13f50ebe80390e0730d1b7afb)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/114097
Tested-by: Michael Stahl <michael.stahl@allotropia.de>
Reviewed-by: Michael Stahl <michael.stahl@allotropia.de>

Change-Id: I3a3f1efe6d7ed28e05dc159a86abc3d702cc272b

1 files changed, 0 insertions, 0 deletions

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