keybindings: Make MetaKeyPref, MetaKeyCombo and MetaKeyHandler private

There's no need for these to be public and keeping them all together
in the same header makes it easier when reading the code.

https://bugzilla.gnome.org/show_bug.cgi?id=725588

src/core/keybindings-private.h

@@ -30,6 +30,7 @@
 #include <gio/gio.h>
 #include <meta/keybindings.h>
 
+typedef struct _MetaKeyHandler MetaKeyHandler;
 struct _MetaKeyHandler
 {
   char *name;
@@ -51,6 +52,44 @@ struct _MetaKeyBinding
   MetaKeyHandler *handler;
 };
 
+/**
+ * MetaKeyCombo:
+ * @keysym: keysym
+ * @keycode: keycode
+ * @modifiers: modifiers
+ */
+typedef struct _MetaKeyCombo MetaKeyCombo;
+struct _MetaKeyCombo
+{
+  unsigned int keysym;
+  unsigned int keycode;
+  MetaVirtualModifier modifiers;
+};
+
+typedef struct
+{
+  char *name;
+  GSettings *settings;
+
+  MetaKeyBindingAction action;
+
+  /*
+   * A list of MetaKeyCombos. Each of them is bound to
+   * this keypref. If one has keysym==modifiers==0, it is
+   * ignored.
+   */
+  GSList *bindings;
+
+  /* for keybindings that can have shift or not like Alt+Tab */
+  gboolean      add_shift:1;
+
+  /* for keybindings that apply only to a window */
+  gboolean      per_window:1;
+
+  /* for keybindings not added with meta_display_add_keybinding() */
+  gboolean      builtin:1;
+} MetaKeyPref;
+
 void     meta_display_init_keys             (MetaDisplay *display);
 void     meta_display_shutdown_keys         (MetaDisplay *display);
 void     meta_screen_grab_keys              (MetaScreen  *screen);
@@ -78,5 +117,8 @@ gboolean meta_prefs_add_keybinding          (const char           *name,
 
 gboolean meta_prefs_remove_keybinding       (const char    *name);
 
+GList *meta_prefs_get_keybindings (void);
+void meta_prefs_get_overlay_binding (MetaKeyCombo *combo);
+const char *meta_prefs_get_iso_next_group_option (void);
 
 #endif

src/core/prefs.c

@@ -2154,11 +2154,6 @@ meta_prefs_remove_keybinding (const char *name)
   return TRUE;
 }
 
-/**
- * meta_prefs_get_keybindings:
- *
- * Returns: (element-type MetaKeyPref) (transfer container):
- */
 GList *
 meta_prefs_get_keybindings ()
 {