fix crash on exporting kde140265-1.doc to ODT

properties.pSGlobalShell can be legitimately 0 here.

No testcase, for some reason the export does not crash if it's done by
CppunitTest_sw_filters_test or CppunitTest_sw_odfexport; but it does
crash with '--headless --convert-to odt kde140265-1.doc'.

Change-Id: I50936f9e5236763cc987aba14d8fc897c4b789bf
(cherry picked from commit 4cd3f9a7)

sw/source/core/layout/paintfrm.cxx

@@ -1509,7 +1509,7 @@ static void lcl_CalcBorderRect( SwRect &rRect, const SwFrm *pFrm,
         }
     }
 
-    ::SwAlignRect( rRect, properties.pSGlobalShell, properties.pSGlobalShell->GetOut() );
+    ::SwAlignRect( rRect, properties.pSGlobalShell, properties.pSGlobalShell ? properties.pSGlobalShell->GetOut() : 0 );
 }
 
 /**