More stubbing out. With this and the rest of Linux pending, test_shell links.

webkit/port/platform/chromium/RenderThemeGtk.cpp

 /*
  * Copyright (C) 2007 Apple Inc.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2008 Collabora Ltd.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 418 matching lines @@
 
     return time / 2000.;
 }
 
 void RenderThemeGtk::systemFont(int, FontDescription&) const
 {
     // If you remove this notImplemented(), replace it with an comment that explains why.
     notImplemented();
 }
 
-void RenderTheme::systemFont(int, Document*, FontDescription&) const
+void RenderThemeGtk::systemFont(int, Document*, FontDescription&) const
 {
     notImplemented();
 }
 
 static void gtkStyleSetCallback(GtkWidget* widget, GtkStyle* previous, RenderTheme* renderTheme)
 {
     // FIXME: Make sure this function doesn't get called many times for a single GTK+ style change signal.
     renderTheme->platformColorsDidChange();
 }
 
@@ skipping 30 matching lines @@
 
     m_gtkTreeView = gtk_tree_view_new();
     g_signal_connect(m_gtkTreeView, "style-set", G_CALLBACK(gtkStyleSetCallback), theme());
     gtk_container_add(gtkContainer(), m_gtkTreeView);
     gtk_widget_realize(m_gtkTreeView);
 
     return m_gtkTreeView;
 }
 
 }