sw content controls: allow no list items in a dropdown

- Replace SwContentControl::HasListItems(), which assumed that the type
is dropdown if we have list items. This is not valid, it's OK to have
a dropdown with no list items. Add a GetDropDown() instead to check
for the type, explicitly.

- UNO API sets the dropdown bit when list items are set and the type is
not expilcitly combo box or drop down, to keep backwards
compatibility with existing documents.

- No change to the edit shell, SwDropDownContentControlButton already
checked if items are empty and used STR_DROP_DOWN_EMPTY_LIST in that
case, but that was dead code previously.

- ODT & DOCX filters are now updated, ODF has a new
<loext:content-control loext:dropdown="..."> attribute to specify that
the type is a dropdown, explicitly.

Change-Id: Id577ba9639151549a8f953aab31685a73a898504
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/142491
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins

1 files changed, 6 insertions, 0 deletions

diff --git a/schema/libreoffice/OpenDocument-v1.3+libreoffice-schema.rng b/schema/libreoffice/OpenDocument-v1.3+libreoffice-schema.rng
index d475e90319b4..3b2e0d4b2bbc 100644
--- a/schema/libreoffice/OpenDocument-v1.3+libreoffice-schema.rng
+++ b/schema/libreoffice/OpenDocument-v1.3+libreoffice-schema.rng
@@ -2993,6 +2993,12 @@ xmlns:loext="urn:org:documentfoundation:names:experimental:office:xmlns:loext:1.
         </rng:attribute>
       </rng:optional>
       <rng:optional>
+        <!-- default value: false -->
+        <rng:attribute name="loext:dropdown">
+          <rng:ref name="boolean"/>
+        </rng:attribute>
+      </rng:optional>
+      <rng:optional>
         <rng:attribute name="loext:alias">
           <rng:ref name="string"/>
         </rng:attribute>