[Android] Upstream ChromeBrowserProvider, the Android port ContentProvider implementation.

chrome/browser/android/provider/bookmark_model_observer_task.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CHROME_BROWSER_BOOKMARKS_BASE_BOOKMARK_MODEL_OBSERVER_H_
-#define CHROME_BROWSER_BOOKMARKS_BASE_BOOKMARK_MODEL_OBSERVER_H_
+#ifndef CHROME_BROWSER_ANDROID_PROVIDER_BOOKMARK_MODEL_OBSERVER_TASK_H_
+#define CHROME_BROWSER_ANDROID_PROVIDER_BOOKMARK_MODEL_OBSERVER_TASK_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "chrome/browser/bookmarks/bookmark_model_observer.h"
 
-// Base class for a BookmarkModelObserver implementation. All mutations of the
-// model funnel into the method BookmarkModelChanged.
-class BaseBookmarkModelObserver : public BookmarkModelObserver {
+// Base class for synchronous tasks that involve the bookmark model.
+// Ensures the model has been loaded before accessing it.
+// Must not be created from the UI thread.
+class BookmarkModelTask {
  public:
-  BaseBookmarkModelObserver() {}
+  explicit BookmarkModelTask(BookmarkModel* model);
+  BookmarkModel* model() const;
 
-  virtual void BookmarkModelChanged() = 0;
+ private:
+  BookmarkModel* model_;
+
+  DISALLOW_COPY_AND_ASSIGN(BookmarkModelTask);
+};
+
+// Base class for bookmark model tasks that observe for model updates.
+class BookmarkModelObserverTask : public BookmarkModelTask,
+                                  public BookmarkModelObserver {
+ public:
+  explicit BookmarkModelObserverTask(BookmarkModel* bookmark_model);
+  virtual ~BookmarkModelObserverTask();
 
   // BookmarkModelObserver:
   virtual void Loaded(BookmarkModel* model, bool ids_reassigned) OVERRIDE;
-  virtual void BookmarkModelBeingDeleted(BookmarkModel* model) OVERRIDE;
   virtual void BookmarkNodeMoved(BookmarkModel* model,
                                  const BookmarkNode* old_parent,
                                  int old_index,
                                  const BookmarkNode* new_parent,
                                  int new_index) OVERRIDE;
   virtual void BookmarkNodeAdded(BookmarkModel* model,
                                  const BookmarkNode* parent,
                                  int index) OVERRIDE;
   virtual void BookmarkNodeRemoved(BookmarkModel* model,
                                    const BookmarkNode* parent,
                                    int old_index,
                                    const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkNodeChanged(BookmarkModel* model,
                                    const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkNodeFaviconChanged(BookmarkModel* model,
                                           const BookmarkNode* node) OVERRIDE;
   virtual void BookmarkNodeChildrenReordered(BookmarkModel* model,
                                              const BookmarkNode* node) OVERRIDE;
 
- protected:
-  virtual ~BaseBookmarkModelObserver() {}
-
  private:
-  DISALLOW_COPY_AND_ASSIGN(BaseBookmarkModelObserver);
+  DISALLOW_COPY_AND_ASSIGN(BookmarkModelObserverTask);
 };
 
-#endif  // CHROME_BROWSER_BOOKMARKS_BASE_BOOKMARK_MODEL_OBSERVER_H_
+#endif  // CHROME_BROWSER_ANDROID_PROVIDER_BOOKMARK_MODEL_OBSERVER_TASK_H_