a11y: Add the supported accessibility roles

The list of roles is taken from the WAI-ARIA 1.2 specification:

  https://w3c.github.io/aria/

Some of these roles do not make entirely sense from a GTK application
perspective, but we can remove them before finalizing the API.

gtk/gtkenums.h

@@ -1150,4 +1150,154 @@ typedef enum {
   GTK_SYSTEM_SETTING_ICON_THEME
 } GtkSystemSetting;
 
+/**
+ * GtkAccessibleRole:
+ * @GTK_ACCESSIBLE_ROLE_ALERT: FIXME
+ * @GTK_ACCESSIBLE_ROLE_ALERT_DIALOG: FIXME
+ * @GTK_ACCESSIBLE_ROLE_APPLICATION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_ARTICLE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_BANNER: FIXME
+ * @GTK_ACCESSIBLE_ROLE_BUTTON: FIXME
+ * @GTK_ACCESSIBLE_ROLE_CHECKBOX: FIXME
+ * @GTK_ACCESSIBLE_ROLE_COLUMN_HEADER: FIXME
+ * @GTK_ACCESSIBLE_ROLE_COMBOBOX: FIXME
+ * @GTK_ACCESSIBLE_ROLE_COMMAND: FIXME
+ * @GTK_ACCESSIBLE_ROLE_COMPLEMENTARY: FIXME
+ * @GTK_ACCESSIBLE_ROLE_COMPOSITE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_CONTENT_INFO: FIXME
+ * @GTK_ACCESSIBLE_ROLE_DEFINITION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_DIALOG: FIXME
+ * @GTK_ACCESSIBLE_ROLE_DIRECTORY: FIXME
+ * @GTK_ACCESSIBLE_ROLE_DOCUMENT: FIXME
+ * @GTK_ACCESSIBLE_ROLE_FORM: FIXME
+ * @GTK_ACCESSIBLE_ROLE_GRID: FIXME
+ * @GTK_ACCESSIBLE_ROLE_GRID_CELL: FIXME
+ * @GTK_ACCESSIBLE_ROLE_GROUP: FIXME
+ * @GTK_ACCESSIBLE_ROLE_HEADING: FIXME
+ * @GTK_ACCESSIBLE_ROLE_IMG: FIXME
+ * @GTK_ACCESSIBLE_ROLE_INPUT: FIXME
+ * @GTK_ACCESSIBLE_ROLE_LANDMARK: FIXME
+ * @GTK_ACCESSIBLE_ROLE_LINK: FIXME
+ * @GTK_ACCESSIBLE_ROLE_LIST_BOX: FIXME
+ * @GTK_ACCESSIBLE_ROLE_LIST_ITEM: FIXME
+ * @GTK_ACCESSIBLE_ROLE_LOG: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MAIN: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MARQUEE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MATH: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MENU: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MENU_BAR: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MENU_ITEM: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MENU_ITEM_CHECKBOX: FIXME
+ * @GTK_ACCESSIBLE_ROLE_MENU_ITEM_RADIO: FIXME
+ * @GTK_ACCESSIBLE_ROLE_NAVIGATION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_NOTE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_OPTION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_PRESENTATION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_PROGRESS_BAR: FIXME
+ * @GTK_ACCESSIBLE_ROLE_RADIO: FIXME
+ * @GTK_ACCESSIBLE_ROLE_RADIO_GROUP: FIXME
+ * @GTK_ACCESSIBLE_ROLE_RANGE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_REGION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_ROW: FIXME
+ * @GTK_ACCESSIBLE_ROLE_ROW_GROUP: FIXME
+ * @GTK_ACCESSIBLE_ROLE_ROW_HEADER: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SCROLLBAR: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SEARCH: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SECTION: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SECTION_HEAD: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SELECT: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SEPARATOR: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SLIDER: FIXME
+ * @GTK_ACCESSIBLE_ROLE_SPIN_BUTTON: FIXME
+ * @GTK_ACCESSIBLE_ROLE_STATUS: FIXME
+ * @GTK_ACCESSIBLE_ROLE_STRUCTURE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TAB: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TAB_LIST: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TAB_PANEL: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TEXT_BOX: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TIMER: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TOOLBAR: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TOOLTIP: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TREE: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TREE_GRID: FIXME
+ * @GTK_ACCESSIBLE_ROLE_TREE_ITEM: FIXME
+ * @GTK_ACCESSIBLE_ROLE_WIDGET: FIXME
+ * @GTK_ACCESSIBLE_ROLE_WINDOW: FIXME
+ *
+ * The accessible role for a #GtkAccessible implementation.
+ */
+typedef enum {
+  GTK_ACCESSIBLE_ROLE_ALERT,
+  GTK_ACCESSIBLE_ROLE_ALERT_DIALOG,
+  GTK_ACCESSIBLE_ROLE_APPLICATION,
+  GTK_ACCESSIBLE_ROLE_ARTICLE,
+  GTK_ACCESSIBLE_ROLE_BANNER,
+  GTK_ACCESSIBLE_ROLE_BUTTON,
+  GTK_ACCESSIBLE_ROLE_CHECKBOX,
+  GTK_ACCESSIBLE_ROLE_COLUMN_HEADER,
+  GTK_ACCESSIBLE_ROLE_COMBOBOX,
+  GTK_ACCESSIBLE_ROLE_COMMAND,
+  GTK_ACCESSIBLE_ROLE_COMPLEMENTARY,
+  GTK_ACCESSIBLE_ROLE_COMPOSITE,
+  GTK_ACCESSIBLE_ROLE_CONTENT_INFO,
+  GTK_ACCESSIBLE_ROLE_DEFINITION,
+  GTK_ACCESSIBLE_ROLE_DIALOG,
+  GTK_ACCESSIBLE_ROLE_DIRECTORY,
+  GTK_ACCESSIBLE_ROLE_DOCUMENT,
+  GTK_ACCESSIBLE_ROLE_FORM,
+  GTK_ACCESSIBLE_ROLE_GRID,
+  GTK_ACCESSIBLE_ROLE_GRID_CELL,
+  GTK_ACCESSIBLE_ROLE_GROUP,
+  GTK_ACCESSIBLE_ROLE_HEADING,
+  GTK_ACCESSIBLE_ROLE_IMG,
+  GTK_ACCESSIBLE_ROLE_INPUT,
+  GTK_ACCESSIBLE_ROLE_LANDMARK,
+  GTK_ACCESSIBLE_ROLE_LINK,
+  GTK_ACCESSIBLE_ROLE_LIST_BOX,
+  GTK_ACCESSIBLE_ROLE_LIST_ITEM,
+  GTK_ACCESSIBLE_ROLE_LOG,
+  GTK_ACCESSIBLE_ROLE_MAIN,
+  GTK_ACCESSIBLE_ROLE_MARQUEE,
+  GTK_ACCESSIBLE_ROLE_MATH,
+  GTK_ACCESSIBLE_ROLE_MENU,
+  GTK_ACCESSIBLE_ROLE_MENU_BAR,
+  GTK_ACCESSIBLE_ROLE_MENU_ITEM,
+  GTK_ACCESSIBLE_ROLE_MENU_ITEM_CHECKBOX,
+  GTK_ACCESSIBLE_ROLE_MENU_ITEM_RADIO,
+  GTK_ACCESSIBLE_ROLE_NAVIGATION,
+  GTK_ACCESSIBLE_ROLE_NOTE,
+  GTK_ACCESSIBLE_ROLE_OPTION,
+  GTK_ACCESSIBLE_ROLE_PRESENTATION,
+  GTK_ACCESSIBLE_ROLE_PROGRESS_BAR,
+  GTK_ACCESSIBLE_ROLE_RADIO,
+  GTK_ACCESSIBLE_ROLE_RADIO_GROUP,
+  GTK_ACCESSIBLE_ROLE_RANGE,
+  GTK_ACCESSIBLE_ROLE_REGION,
+  GTK_ACCESSIBLE_ROLE_ROW,
+  GTK_ACCESSIBLE_ROLE_ROW_GROUP,
+  GTK_ACCESSIBLE_ROLE_ROW_HEADER,
+  GTK_ACCESSIBLE_ROLE_SCROLLBAR,
+  GTK_ACCESSIBLE_ROLE_SEARCH,
+  GTK_ACCESSIBLE_ROLE_SECTION,
+  GTK_ACCESSIBLE_ROLE_SECTION_HEAD,
+  GTK_ACCESSIBLE_ROLE_SELECT,
+  GTK_ACCESSIBLE_ROLE_SEPARATOR,
+  GTK_ACCESSIBLE_ROLE_SLIDER,
+  GTK_ACCESSIBLE_ROLE_SPIN_BUTTON,
+  GTK_ACCESSIBLE_ROLE_STATUS,
+  GTK_ACCESSIBLE_ROLE_STRUCTURE,
+  GTK_ACCESSIBLE_ROLE_TAB,
+  GTK_ACCESSIBLE_ROLE_TAB_LIST,
+  GTK_ACCESSIBLE_ROLE_TAB_PANEL,
+  GTK_ACCESSIBLE_ROLE_TEXT_BOX,
+  GTK_ACCESSIBLE_ROLE_TIMER,
+  GTK_ACCESSIBLE_ROLE_TOOLBAR,
+  GTK_ACCESSIBLE_ROLE_TOOLTIP,
+  GTK_ACCESSIBLE_ROLE_TREE,
+  GTK_ACCESSIBLE_ROLE_TREE_GRID,
+  GTK_ACCESSIBLE_ROLE_TREE_ITEM,
+  GTK_ACCESSIBLE_ROLE_WIDGET,
+  GTK_ACCESSIBLE_ROLE_WINDOW
+} GtkAccessibleRole;
+
 #endif /* __GTK_ENUMS_H__ */