mash: Use mojo for ShelfItemDelegate and [app] MenuItem.

ash/public/interfaces/shelf.mojom

Index: ash/public/interfaces/shelf.mojom
diff --git a/ash/public/interfaces/shelf.mojom b/ash/public/interfaces/shelf.mojom
index 020a5577d5bf1cfe4b37ce6f58b9293df4d87b65..f0d0d636d6e857e11cf3d4ed246c8dc2b7b2f670 100644
--- a/ash/public/interfaces/shelf.mojom
+++ b/ash/public/interfaces/shelf.mojom
@@ -4,7 +4,19 @@
 
 module ash.mojom;
 
+import "mojo/common/string16.mojom";
 import "skia/public/interfaces/bitmap.mojom";
+import "ui/events/mojo/event.mojom";
+
+// The actions that may be performed when a shelf item is selected.
+// These values match ash::ShelfAction.
+enum ShelfAction {
+  NONE,              // No action was taken.
+  WINDOW_CREATED,    // A new window was created.
+  WINDOW_ACTIVATED,  // An existing inactive window was activated.
+  WINDOW_MINIMIZED,  // The currently active window was minimized.
+  APP_LIST_SHOWN,    // The app list launcher menu was shown.
+};
 
 // These values match ash::ShelfAlignment.
 enum ShelfAlignment { BOTTOM, LEFT, RIGHT, BOTTOM_LOCKED, };
@@ -12,6 +24,14 @@ enum ShelfAlignment { BOTTOM, LEFT, RIGHT, BOTTOM_LOCKED, };
 // These values match ash::ShelfAutoHideBehavior.
 enum ShelfAutoHideBehavior { ALWAYS, NEVER, HIDDEN, };
 
+// Source of the launch or activation request, for tracking.
+// These values match ash::ShelfLaunchSource.
+enum ShelfLaunchSource {
+  UNKNOWN,          // The item was launched from outside the app list.
+  APP_LIST,         // The item was launched from a generic app list view.
+  APP_LIST_SEARCH,  // The item was launched from an app list search view.
+};
+
 // The Shelf controller allows clients (eg. Chrome) to control the ash shelf.
 interface ShelfController {
   // Observers are immediately notified of the current shelf states when added.
@@ -34,34 +54,41 @@ interface ShelfObserver {
   OnAutoHideBehaviorChanged(ShelfAutoHideBehavior auto_hide, int64 display_id);
 };
 
-// ShelfItemDelegate handles command execution and observes shelf item changes.
+// ShelfItemDelegate handles shelf item selection, menu command execution, etc.
 interface ShelfItemDelegate {
-  // Called when a pinned shelf item is invoked without an open window.
-  LaunchItem();
-
-  // Called on invocation of a shelf item's context menu command.
+  // Called when the user selects a shelf item. The event, display, and source
+  // info should be provided if known; some implementations use these arguments.
+  // Defaults: (nullptr, kInvalidDisplayId, LAUNCH_FROM_UNKNOWN)
+  // The callback reports the action taken and any app menu items to show.
+  //
+  // NOTE: This codepath is not currently used for context menu triggering.
+  // TODO(msw): Remove |display_id| once panels are removed. crbug.com/691099
+  ItemSelected(ui.mojom.Event event,
+               int64 display_id,
+               ShelfLaunchSource source) => (ShelfAction action,
+                                             array<MenuItem> menu_items);
+
+  // Called on invocation of a shelf item's context or application menu command.
   ExecuteCommand(uint32 command_id, int32 event_flags);
 
-  // Called when a shelf item is pinned or unpinned.
-  ItemPinned();
-  ItemUnpinned();
-
-  // Called when a pinned shelf item is reordered.
-  // |order| is the index of the item on the shelf.
-  ItemReordered(uint32 order);
+  // Closes all windows associated with this shelf item.
+  Close();
 };
 
-// ContextMenuItems may be used to supplement ash shelf item context menus.
-struct ContextMenuItem {
+// MenuItems are used to populate application menus for shelf items.
+// Note: Some menus only support a subset of these item features (eg. no icons).
+// Note: These are not yet used for shelf item or ash shell context menus.
+struct MenuItem {
   enum Type { ITEM, CHECK, RADIO, SEPARATOR, SUBMENU };
 
-  Type type;
-  uint32 command_id;
-  string? label;
-  array<ContextMenuItem>? submenu;
-  bool enabled;
-  bool checked;
-  uint32 radio_group_id;
+  Type type;                         // The type of the menu item.
+  uint32 command_id;                 // The client's arbitrary item command id.
+  mojo.common.mojom.String16 label;  // The string label, may be empty.

[James Cook, 2017/03/10 16:56:01]

Nice docs throughout this file, btw. Details like this "string may be empty" are
really valuable to me.

[msw, 2017/03/10 20:44:45]

Acknowledged.

+  skia.mojom.Bitmap image;           // The image icon, may be null.
+  array<MenuItem>? submenu;          // The optional nested submenu item list.
+  bool enabled;                      // The enabled state.
+  bool checked;                      // The checked state.
+  uint32 radio_group_id;             // The radio group id.
 };
 
 // ShelfItem contains the basic fields needed to pin shortcut items.
@@ -76,5 +103,5 @@ struct ShelfItem {
   skia.mojom.Bitmap image;
 
   // Additional context menu items (eg. 'New Incognito Window').
-  array<ContextMenuItem>? context_menu_items;
+  array<MenuItem>? context_menu_items;
 };