loplugin:useuniqueptr in SdrEdgeObj

Change-Id: I457520760d182fdd4f89cb7c7a4ea2c0e514e0c4
Reviewed-on: https://gerrit.libreoffice.org/49273Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

include/svx/svdoedge.hxx

@@ -142,7 +142,7 @@ protected:
     SdrObjConnection            aCon1;  // Connection status of the beginning of the line
     SdrObjConnection            aCon2;  // Connection status of the end of the line
 
-    XPolygon*                   pEdgeTrack;
+    std::unique_ptr<XPolygon>   pEdgeTrack;
     sal_uInt16                  nNotifyingCount; // Locking
     SdrEdgeInfoRec              aEdgeInfo;
 

svx/source/svdraw/svdoedge.cxx

@@ -173,15 +173,13 @@ SdrEdgeObj::SdrEdgeObj()
 {
     bClosedObj=false;
     bIsEdge=true;
-    pEdgeTrack=new XPolygon;
-
+    pEdgeTrack.reset(new XPolygon);
 }
 
 SdrEdgeObj::~SdrEdgeObj()
 {
     SdrEdgeObj::DisconnectFromNode(true);
     SdrEdgeObj::DisconnectFromNode(false);
-    delete pEdgeTrack;
 }
 
 void SdrEdgeObj::ImpSetAttrToEdgeInfo()