Restore better perimeter/infill overlap for solid surfaces

lib/Slic3r/Fill/Rectilinear.pm

@@ -51,7 +51,7 @@ sub fill_surface {
     }
     
     # connect lines
-    if ($params{density} < 1) {
+    {
         my $collection = Slic3r::ExtrusionPath::Collection->new(
             paths => [ map Slic3r::ExtrusionPath->cast([ @$_ ], role => 'bogus'), @paths ],
         );