introspection: Build with --warn-all --warn-error

* Use --warn-all, --warn-error
* Fix various broken gtk-doc
* Drop unused shell_get_event_related
* For header defines, we currently require them to end in _H to be skipped
* Drop the no-longer-necessary fix-meta-rectangle.py hack
* Move to the convention of using -private.h for headers that are,
  well, private.
* Add shell-wm-private.h

src/shell-wm-private.h

@@ -0,0 +1,40 @@
+/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
+#ifndef __SHELL_WM_PRIVATE_H__
+#define __SHELL_WM_PRIVATE_H__
+
+#include "shell-wm.h"
+
+G_BEGIN_DECLS
+
+/* These forward along the different effects from GnomeShellPlugin */
+
+void _shell_wm_minimize   (ShellWM      *wm,
+			   MutterWindow *actor);
+void _shell_wm_maximize   (ShellWM      *wm,
+			   MutterWindow *actor,
+			   gint          x,
+			   gint          y,
+			   gint          width,
+			   gint          height);
+void _shell_wm_unmaximize (ShellWM      *wm,
+			   MutterWindow *actor,
+			   gint          x,
+			   gint          y,
+			   gint          width,
+			   gint          height);
+void _shell_wm_map        (ShellWM      *wm,
+			   MutterWindow *actor);
+void _shell_wm_destroy    (ShellWM      *wm,
+			   MutterWindow *actor);
+
+void _shell_wm_switch_workspace (ShellWM              *wm,
+				 gint                  from,
+				 gint                  to,
+				 MetaMotionDirection   direction);
+void _shell_wm_kill_window_effects  (ShellWM              *wm,
+				     MutterWindow         *actor);
+void _shell_wm_kill_switch_workspace (ShellWM              *wm);
+
+G_END_DECLS
+
+#endif /* __SHELL_WM_PRIVATE_H__ */