Fix for a236f831

To get footnotes sorted properly one need to:
  * actually use the comparator class
  * compare on the offsets value (and not there pointers)

Change-Id: Ie86802c7a92602bfbb4d2a603afe06f621e392a3

sw/inc/ftnidx.hxx

@@ -47,7 +47,7 @@ struct CompareSwFtnIdxs
     bool operator()(SwTxtFtn* const& lhs, SwTxtFtn* const& rhs) const;
 };
 
-class SwFtnIdxs : public o3tl::sorted_vector<SwTxtFtn*>
+class SwFtnIdxs : public o3tl::sorted_vector<SwTxtFtn*, CompareSwFtnIdxs>
 {
 public:
     SwFtnIdxs() {}

sw/source/core/doc/ftnidx.cxx

@@ -43,7 +43,7 @@ bool CompareSwFtnIdxs::operator()(SwTxtFtn* const& lhs, SwTxtFtn* const& rhs) co
 {
     sal_uLong nIdxLHS = _SwTxtFtn_GetIndex( lhs );
     sal_uLong nIdxRHS = _SwTxtFtn_GetIndex( rhs );
-    return ( nIdxLHS == nIdxRHS && lhs->GetStart() < rhs->GetStart() ) || nIdxLHS < nIdxRHS;
+    return ( nIdxLHS == nIdxRHS && *lhs->GetStart() < *rhs->GetStart() ) || nIdxLHS < nIdxRHS;
 }
 
 void SwFtnIdxs::UpdateFtn( const SwNodeIndex& rStt )