dr80: #i117511# remove some assertions in xlsx/xlsb import filters

Conflicts:
	sc/source/core/data/document.cxx
	sc/source/core/tool/address.cxx

sc/source/core/data/document.cxx

@@ -5669,7 +5669,10 @@ void ScDocument::EnableUndo( bool bVal )
     // the lock count becomes zero.
 
     if (bVal != GetUndoManager()->IsUndoEnabled())
+    {
         GetUndoManager()->EnableUndo(bVal);
+        if( pDrawLayer ) pDrawLayer->EnableUndo(bVal);
+    }
 
     mbUndoEnabled = bVal;
 }

sc/source/core/data/drwlayer.cxx

@@ -273,6 +273,10 @@ ScDrawLayer::ScDrawLayer( ScDocument* pDocument, const String& rName ) :
     if ( pHitOutlinerPool )
          pHitOutlinerPool->SetPoolDefaultItem(SvxFontHeightItem( 423, 100, EE_CHAR_FONTHEIGHT ));    // 12Pt
 
+    // initial undo mode as in Calc document
+    if( pDoc )
+        EnableUndo( pDoc->IsUndoEnabled() );
+
     //  URL-Buttons haben keinen Handler mehr, machen alles selber
 
     if( !nInst++ )

sc/source/core/tool/address.cxx

@@ -343,13 +343,13 @@ static bool lcl_XL_getExternalDoc( const sal_Unicode** ppErrRet, String& rExtern
         const uno::Sequence< const sheet::ExternalLinkInfo > * pExternalLinks)
 {
     // 1-based, sequence starts with an empty element.
-    if (pExternalLinks && pExternalLinks->getLength() > 1)
+    if (pExternalLinks && pExternalLinks->hasElements())
     {
         // A numeric "document name" is an index into the sequence.
         if (CharClass::isAsciiNumeric( rExternDocName))
         {
             sal_Int32 i = rExternDocName.ToInt32();
-            if (i <= 0 || i >= pExternalLinks->getLength())
+            if (i < 0 || i >= pExternalLinks->getLength())
                 return false;   // with default *ppErrRet
             const sheet::ExternalLinkInfo & rInfo = (*pExternalLinks)[i];
             switch (rInfo.Type)
@@ -366,6 +366,12 @@ static bool lcl_XL_getExternalDoc( const sal_Unicode** ppErrRet, String& rExtern
                         rExternDocName = aStr;
                     }
                     break;
+                    case sheet::ExternalLinkType::SELF :
+                        return false;   // ???
+                    case sheet::ExternalLinkType::SPECIAL :
+                        // silently return nothing (do not assert), caller has to handle this
+                        *ppErrRet = NULL;
+                        return false;
                 default:
                     OSL_TRACE( "ScRange::Parse_XL_Header: unhandled ExternalLinkType %d for index %d",
                             rInfo.Type, i);