[gtk+] Make gtkclipboard.c:clipboard_get_timestamp multi-backend safe

[Alexander Larsson <alexl src gnome org>]

commit 9db4accf9c30e29979e3e012f0a8b3ef624bb690
Author: Alexander Larsson <alexl redhat com>
Date:   Thu Apr 7 20:19:30 2011 +0200

    Make gtkclipboard.c:clipboard_get_timestamp multi-backend safe
    
    We can't just check for the backend defines, we have to do runtime checks too.

 gtk/gtkclipboard.c |   31 ++++++++++++++++++++++++++++---
 1 files changed, 28 insertions(+), 3 deletions(-)
---
diff --git a/gtk/gtkclipboard.c b/gtk/gtkclipboard.c
index e918495..5dc09e5 100644
--- a/gtk/gtkclipboard.c
+++ b/gtk/gtkclipboard.c
@@ -34,6 +34,10 @@
 #include "x11/gdkx.h"
 #endif
 
+#ifdef GDK_WINDOWING_BROADWAY
+#include "broadway/gdkbroadway.h"
+#endif
+
 #ifdef GDK_WINDOWING_WIN32
 #include "win32/gdkwin32.h"
 #endif
@@ -412,14 +416,35 @@ clipboard_get_timestamp (GtkClipboard *clipboard)
 {
   GtkWidget *clipboard_widget = get_clipboard_widget (clipboard->display);
   guint32 timestamp = gtk_get_current_event_time ();
+  GdkWindow *window;
 
   if (timestamp == GDK_CURRENT_TIME)
     {
+      window = gtk_widget_get_window (clipboard_widget);
 #ifdef GDK_WINDOWING_X11
-      timestamp = gdk_x11_get_server_time (gtk_widget_get_window (clipboard_widget));
-#elif defined GDK_WINDOWING_WIN32
-      timestamp = GetMessageTime ();
+      if (GDK_IS_X11_WINDOW (window))
+	{
+	  timestamp = gdk_x11_get_server_time (gtk_widget_get_window (clipboard_widget));
+	}
+      else
 #endif
+#if defined GDK_WINDOWING_WIN32
+      if (GDK_IS_WIN32_WINDOW (window))
+	{
+	  timestamp = GetMessageTime ();
+	}
+      else
+#endif
+#if defined GDK_WINDOWING_BROADWAY
+      if (GDK_IS_BROADWAY_WINDOW (window))
+	{
+	  timestamp = gdk_broadway_get_last_seen_time (window);
+	}
+      else
+#endif
+	{
+	  /* No implementation */
+	}
     }
   else
     {