Preserve highlighted connection through a recalculation

eeschema/sch_edit_frame.cpp

@@ -1297,6 +1297,13 @@ void SCH_EDIT_FRAME::initScreenZoom()
 
 void SCH_EDIT_FRAME::RecalculateConnections( SCH_CLEANUP_FLAGS aCleanupFlags )
 {
+    const SCH_CONNECTION* highlight       = GetHighlightedConnection();
+    SCH_ITEM*             highlightedItem = highlight ? highlight->Parent() : nullptr;
+    SCH_SHEET_PATH highlightPath;
+
+    if( highlight )
+        highlightPath = highlight->Sheet();
+
     SCHEMATIC_SETTINGS& settings = Schematic().Settings();
     SCH_SHEET_LIST      list = Schematic().GetSheets();
 #ifdef PROFILE
@@ -1329,6 +1336,9 @@ void SCH_EDIT_FRAME::RecalculateConnections( SCH_CLEANUP_FLAGS aCleanupFlags )
             };
 
     Schematic().ConnectionGraph()->Recalculate( list, true, &changeHandler );
+
+    if( highlightedItem )
+        SetHighlightedConnection( highlightedItem->Connection( &highlightPath ) );
 }