tdf#144092 pptx export: export endParaRPr for empty shape & cells

Alters ShapeExport::WriteTextBox so that when it is called with an empty
text (on PPTX export) an attempt to export empty text's char properties
(stored in the Shape or Cell's properties directly) made on
ShapeExport::WriteText.

These properties are exported into endParaRPr.

Implementing this caused some tests that contain connector shapes fail
with XML schema validation errors, therefore disabled export of txBody
inside cxnSp tags.

Also adds a unit test that checks roundtrip of empty shape or cell's
endParaRPr.

Change-Id: I3e3feda802f42560fa7fecc9c0b1afe73a900a84
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/138960
Tested-by: Jenkins
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>

0 files changed, 0 insertions, 0 deletions