[gtk] treeview: Fix column visibility check

[Timm Bäder <baedert src gnome org>]

commit c85e2401fa439191fe6151212fffef9e2c2888c0
Author: Timm Bäder <mail baedert org>
Date:   Sun Jul 8 10:32:12 2018 +0200

    treeview: Fix column visibility check
    
    This is still fallout from the bin_window removal. We aren't moving the
    GdkWindow/GdkSurface anymore so we have to account for the scrolling
    ourselves.

 gtk/gtktreeview.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtktreeview.c b/gtk/gtktreeview.c
index cf95a768bb..c437ac75e4 100644
--- a/gtk/gtktreeview.c
+++ b/gtk/gtktreeview.c
@@ -4538,6 +4538,8 @@ gtk_tree_view_bin_snapshot (GtkWidget   *widget,
                            GtkSnapshot *snapshot)
 {
   GtkTreeView *tree_view = GTK_TREE_VIEW (widget);
+  GtkTreeViewPrivate *priv = gtk_tree_view_get_instance_private (tree_view);
+  const int x_scroll_offset = - gtk_adjustment_get_value (priv->hadjustment);
   GtkTreePath *path;
   GtkRBTree *tree;
   GList *list;
@@ -4658,7 +4660,7 @@ gtk_tree_view_bin_snapshot (GtkWidget   *widget,
 
       max_height = gtk_tree_view_get_row_height (tree_view, node);
 
-      cell_offset = 0;
+      cell_offset = x_scroll_offset;
 
       background_area.y = y_offset + clip.y;
       background_area.height = max_height;
@@ -4731,7 +4733,7 @@ gtk_tree_view_bin_snapshot (GtkWidget   *widget,
           else
             flags &= ~GTK_CELL_RENDERER_EXPANDED;
 
-         background_area.x = cell_offset;
+          background_area.x = cell_offset;
          background_area.width = width;
 
           cell_area = background_area;
@@ -4768,6 +4770,9 @@ gtk_tree_view_bin_snapshot (GtkWidget   *widget,
              continue;
            }
 
+          background_area.x -= x_scroll_offset;
+          cell_area.x -= x_scroll_offset;
+
          gtk_tree_view_column_cell_set_cell_data (column,
                                                   tree_view->priv->model,
                                                   &iter,