tdf75573 docx - complete frames before starting alternate streams

An unused odd header was set to be discarded.  The handling of
unregistered frames occurred at the same time, and thus ended up
being discarded as well.

Since a frame shouldn't encompass both the alternate stream
and the current stream, finalize any unfinished frames first.

Change-Id: Ie9123769724da461dd265936aa6b97de7f4dfbbc
Reviewed-on: https://gerrit.libreoffice.org/26972Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>

sw/qa/extras/ooxmlimport/ooxmlimport.cxx

@@ -1732,6 +1732,13 @@ DECLARE_OOXMLIMPORT_TEST(testfdo76583, "fdo76583.docx")
     lcl_countTextFrames( mxComponent, 1 );
 }
 
+DECLARE_OOXMLIMPORT_TEST(testTdf75573, "tdf75573_page1frame.docx")
+{
+    // the problem was that an odd header was defined but not used, flagged as
+    // discardable, and then the unrelated frame was also discarded.
+    lcl_countTextFrames( mxComponent, 1 );
+}
+
 DECLARE_OOXMLIMPORT_TEST(testFdo43093, "fdo43093.docx")
 {
     // The problem was that the direction and alignment are not correct for RTL paragraphs.

writerfilter/source/dmapper/DomainMapper_Impl.cxx

@@ -5246,6 +5246,10 @@ void DomainMapper_Impl::substream(Id rName,
     appendTableHandler();
     getTableManager().startLevel();
 
+    //finalize any waiting frames before starting alternate streams
+    CheckUnregisteredFrameConversion();
+    ExecuteFrameConversion();
+
     //import of page header/footer
 
     switch( rName )