Integrate the Spelling service to Chrome.

chrome/browser/tab_contents/render_view_context_menu.h

Index: chrome/browser/tab_contents/render_view_context_menu.h
===================================================================
--- chrome/browser/tab_contents/render_view_context_menu.h	(revision 98595)
+++ chrome/browser/tab_contents/render_view_context_menu.h	(working copy)
@@ -12,9 +12,11 @@
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
+#include "base/observer_list.h"
 #include "base/string16.h"
 #include "chrome/browser/custom_handlers/protocol_handler_registry.h"
 #include "chrome/browser/extensions/extension_menu_manager.h"
+#include "chrome/browser/tab_contents/render_view_context_menu_observer.h"
 #include "content/common/page_transition_types.h"
 #include "ui/base/models/simple_menu_model.h"
 #include "webkit/glue/context_menu.h"
@@ -22,7 +24,9 @@
 
 class ExtensionMenuItem;
 class Profile;
+class RenderViewHost;
 class TabContents;
+class SpellingMenuObserver;
 
 namespace gfx {
 class Point;
@@ -32,8 +36,75 @@
 struct WebMediaPlayerAction;
 }
 
-class RenderViewContextMenu : public ui::SimpleMenuModel::Delegate {
+// An interface that controls a RenderViewContextMenu instance from observers.
+// This interface is designed mainly for controlling the instance while showing
+// so we can add a context-menu item that takes long time to create its text,
+// such as retrieving the item text from a server. The simplest usage is:
+// 1. Adding an item with temporary text;
+// 2. Posting a background task that creates the item text, and;
+// 3. Calling UpdateMenuItem() in the callback function.
+// The following snippet describes the simple usage that updates a context-menu
+// item with this interface.
+//
+//   class MyTask : public URLFetcher::Delegate {
+//    public:
+//     MyTask(RenderViewContextMenuProxy* proxy, int id)
+//         : proxy_(proxy),
+//           id_(id) {
+//     }
+//     virtual ~MyTask() {
+//     }
+//     virtual void OnURLFetchComplete(const URLFetcher* source,
+//                                     const GURL& url,
+//                                     const net::URLRequestStatus& status,
+//                                     int response,
+//                                     const net::ResponseCookies& cookies,
+//                                     const std::string& data) {
+//       bool enabled = response == 200;
+//       const char* text = enabled ? "OK" : "ERROR";
+//       proxy_->UpdateMenuItem(id_, enabled, ASCIIToUTF16(text));
+//     }
+//     void Start(const GURL* url, net::URLRequestContextGetter* context) {
+//       fetcher_.reset(new URLFetcher(url, URLFetcher::GET, this));
+//       fetcher_->set_request_context(context);
+//       fetcher_->Start();
+//     }
+//
+//    private:
+//     URLFetcher fetcher_;
+//     RenderViewContextMenuProxy* proxy_;
+//     int id_;
+//   };
+//
+//   void RenderViewContextMenu::AppendEditableItems() {
+//     // Add a menu item with temporary text shown while we create the final
+//     // text.
+//     menu_model_.AddItemWithStringId(IDC_MY_ITEM, IDC_MY_TEXT);
+//
+//     // Start a task that creates the final text.
+//     my_task_ = new MyTask(this, IDC_MY_ITEM);
+//     my_task_->Start(...);
+//   }
+//
+class RenderViewContextMenuProxy {
  public:
+  // Add a menu item to a context menu.
+  virtual void AddMenuItem(int command_id, const string16& title) = 0;
+
+  // Update the status and text of the specified context-menu item.
+  virtual void UpdateMenuItem(int command_id,
+                              bool enabled,
+                              const string16& title) = 0;
+
+  // Retrieve the RenderViewHost (or Profile) instance associated with a context
+  // menu, respectively.
+  virtual RenderViewHost* GetRenderViewHost() const = 0;
+  virtual Profile* GetProfile() const = 0;
+};
+
+class RenderViewContextMenu : public ui::SimpleMenuModel::Delegate,
+                              public RenderViewContextMenuProxy {
+ public:
   static const size_t kMaxExtensionItemTitleLength;
   static const size_t kMaxSelectionTextLength;
 
@@ -55,6 +126,14 @@
   virtual void MenuWillShow(ui::SimpleMenuModel* source) OVERRIDE;
   virtual void MenuClosed(ui::SimpleMenuModel* source) OVERRIDE;
 
+  // RenderViewContextMenuDelegate implementation.
+  virtual void AddMenuItem(int command_id, const string16& title) OVERRIDE;
+  virtual void UpdateMenuItem(int command_id,
+                              bool enabled,
+                              const string16& title) OVERRIDE;
+  virtual RenderViewHost* GetRenderViewHost() const;
+  virtual Profile* GetProfile() const;
+
  protected:
   void InitMenu();
 
@@ -170,6 +249,12 @@
   ScopedVector<ui::SimpleMenuModel> extension_menu_models_;
   scoped_refptr<ProtocolHandlerRegistry> protocol_handler_registry_;
 
+  // An observer that handles a spelling-menu items.
+  scoped_ptr<SpellingMenuObserver> spelling_menu_observer_;
+
+  // Our observers.
+  mutable ObserverList<RenderViewContextMenuObserver> observers_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderViewContextMenu);
 };