[gtkmm] Gtk::Snapshot: Update a comment

[Kjell Ahlstedt <kjellahl src gnome org>]

commit 0a6be63f5c0b578506dcad9c60d9edcbf11b04ac
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Wed Jul 26 10:43:02 2017 +0200

    Gtk::Snapshot: Update a comment

 gtk/src/snapshot.hg |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/gtk/src/snapshot.hg b/gtk/src/snapshot.hg
index 81858eb..7b20d0e 100644
--- a/gtk/src/snapshot.hg
+++ b/gtk/src/snapshot.hg
@@ -31,7 +31,7 @@ namespace Gtk
 /** Auxiliary object for snapshots.
  *
  * %Snapshot is an auxiliary object that assists in creating GskRenderNodes
- * in the Gtk::WidgetCustomRenderer::snapshot_vfunc(). It functions in a similar way to
+ * in the Gtk::WidgetCustomSnapshot::snapshot_vfunc(). It functions in a similar way to
  * a cairo context, and maintains a stack of render nodes and their associated
  * transformations.
  *
@@ -39,7 +39,7 @@ namespace Gtk
  * operates on. Use the push() and pop() functions to change the current node.
  *
  * The only way to obtain a %Snapshot object is as an argument to
- * the Gtk::WidgetCustomRenderer::snapshot_vfunc().
+ * Gtk::WidgetCustomSnapshot::snapshot_vfunc().
  *
  * @newin{3,90}
  */