Completed the code path from AndroidProviderService to HistoryBackend.

chrome/browser/history/android/android_history_provider_service.h

Index: chrome/browser/history/android/android_history_provider_service.h
diff --git a/chrome/browser/history/android/android_history_provider_service.h b/chrome/browser/history/android/android_history_provider_service.h
new file mode 100644
index 0000000000000000000000000000000000000000..e9245136e1947b6c11ae0857c0a17f339449ee58
--- /dev/null
+++ b/chrome/browser/history/android/android_history_provider_service.h
@@ -0,0 +1,178 @@
+// 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_HISTORY_ANDROID_ANDROID_HISTORY_PROVIDER_SERVICE_H_
+#define CHROME_BROWSER_HISTORY_ANDROID_ANDROID_HISTORY_PROVIDER_SERVICE_H_
+
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
+#include "chrome/browser/cancelable_request.h"
+#include "chrome/browser/history/android/android_history_types.h"
+#include "sql/statement.h"
+
+class Profile;
+
+// This class provides the methods to communicate with history backend service
+// for the Android content provider.
+// The methods of this class must run on the UI thread to cooperate with the
+// BookmarkModel task posted in the DB thread.
+class AndroidHistoryProviderService : public CancelableRequestProvider {
+ public:
+  explicit AndroidHistoryProviderService(Profile* profile);
+  virtual ~AndroidHistoryProviderService();
+
+  // The callback definitions ------------------------------------------------
+  typedef base::Callback<void(
+                    Handle,                // handle
+                    bool,                  // true if the query succeeded.
+                    history::AndroidStatement*)>  // the result of query
+                    QueryCallback;
+  typedef CancelableRequest<QueryCallback> QueryRequest;
+
+  typedef base::Callback<void(
+                    Handle,                // handle
+                    bool,                  // true if the update succeeded.
+                    int)>                  // the number of row updated.
+                    UpdateCallback;
+  typedef CancelableRequest<UpdateCallback> UpdateRequest;
+
+  typedef base::Callback<void(
+                    Handle,                // handle
+                    bool,                  // true if the insert succeeded.
+                    int64)>                // the id of inserted row.
+                    InsertCallback;
+  typedef CancelableRequest<InsertCallback> InsertRequest;
+
+  typedef base::Callback<void(
+                    Handle,                // handle
+                    bool,                  // true if the deletion succeeded.
+                    int)>                  // the number of row deleted.
+                    DeleteCallback;
+  typedef CancelableRequest<DeleteCallback> DeleteRequest;
+
+  typedef base::Callback<void(
+                    Handle,                // handle
+                    int)>                  // the new position.
+                    MoveStatementCallback;
+  typedef CancelableRequest<MoveStatementCallback> MoveStatementRequest;
+
+  // History and Bookmarks ----------------------------------------------------
+  //
+  // Runs the given query on history backend, and invokes the |callback| to
+  // return the result.
+  //
+  // |projections| is the vector of the result columns.
+  // |selection| is the SQL WHERE clause without 'WHERE'.
+  // |selection_args| is the arguments for WHERE clause.
+  // |sort_order| is the SQL ORDER clause.
+  void QueryHistoryAndBookmarks(

[sky, 2012/04/27 21:37:22]

How come none of these return a Handle? Do you never need to cancel them?

[michaelbai, 2012/04/27 23:26:04]

It was there, it seemed that someone removed them during the merge.

On 2012/04/27 21:37:22, sky wrote:

+      const std::vector<history::HistoryAndBookmarkRow::ColumnID>& projections,
+      const std::string selection,

[sky, 2012/04/27 21:37:22]

const std::string&

[michaelbai, 2012/04/27 23:26:04]

Done.

+      const std::vector<string16>& selection_args,
+      const std::string sort_order,

[sky, 2012/04/27 21:37:22]

const std::string&

[michaelbai, 2012/04/27 23:26:04]

Done.

+      CancelableRequestConsumerBase* consumer,
+      const QueryCallback& callback);
+
+  // Runs the given update and the number of the row updated is returned from

[sky, 2012/04/27 21:37:22]

from -> to the

[michaelbai, 2012/04/27 23:26:04]

Done.

+  // |callback| on success.
+  //
+  // |row| is the value to update.
+  // |selection| is the SQL WHERE clause without 'WHERE'.
+  // |selection_args| is the arguments for the WHERE clause.
+  void UpdateHistoryAndBookmarks(const history::HistoryAndBookmarkRow& row,
+                                 const std::string& selection,
+                                 const std::vector<string16>& selection_args,
+                                 CancelableRequestConsumerBase* consumer,
+                                 const UpdateCallback& callback);
+
+  // Deletes the specified rows and invokes the |callback| to return the number
+  // of row deleted on success.
+  //
+  // |selection| is the SQL WHERE clause without 'WHERE'.
+  // |selection_args| is the arguments for the WHERE clause.
+  //
+  // if |selection| is empty all history and bookmarks are deleted.
+  void DeleteHistoryAndBookmarks(const std::string& selection,
+                                 const std::vector<string16>& selection_args,
+                                 CancelableRequestConsumerBase* consumer,
+                                 const DeleteCallback& callback);
+
+  // Inserts the given values into history backend, and invokes the |callback|
+  // to return the result.
+  void InsertHistoryAndBookmark(const history::HistoryAndBookmarkRow& values,
+                                CancelableRequestConsumerBase* consumer,
+                                const InsertCallback& callback);
+
+  // Deletes the matched history and invokes |callback| to return the number of
+  // the row deleted from the |callback|.
+  void DeleteHistory(const std::string& selection,
+                     const std::vector<string16>& selection_args,
+                     CancelableRequestConsumerBase* consumer,
+                     const DeleteCallback& callback);
+
+  // Statement ----------------------------------------------------------------
+  // Moved the statement's current row from |current_pos| to |destination| in DB

[sky, 2012/04/27 21:37:22]

Moved -> Moves

[michaelbai, 2012/04/27 23:26:04]

Done.

+  // thread. The new position will be returned in the callback and might not be

[sky, 2012/04/27 21:37:22]

will be -> is returned to the callback.
The result supplied to the callback is constrained by the number of rows.

[michaelbai, 2012/04/27 23:26:04]

Done.

+  // the |destination| if the |destination| isn't less than the count of rows.
+  void MoveStatement(history::AndroidStatement* statement,
+                     int current_pos,
+                     int destination,
+                     CancelableRequestConsumerBase* consumer,
+                     const MoveStatementCallback& callback);
+
+  // Asks to close the statement in database thread. The ownership of

[sky, 2012/04/27 21:37:22]

Closes the statement on the db thread. AndroidHistoryProviderService takes
ownership of |statement|.

[michaelbai, 2012/04/27 23:26:04]

Done.

+  // |statement| is transferred.
+  void CloseStatement(history::AndroidStatement* statement);
+
+  // Search term --------------------------------------------------------------
+  // Inserts the given valus and return the SearchTermID of the inserted row

[sky, 2012/04/27 21:37:22]

valus -> values
return -> returns

[michaelbai, 2012/04/27 23:26:04]

Done.

+  // from the |callback| on success.
+  void InsertSearchTerm(const history::SearchRow& row,
+                        CancelableRequestConsumerBase* consumer,
+                        const InsertCallback& callback);
+
+  // Runs the given update and returns the number of the updated rows from the

[sky, 2012/04/27 21:37:22]

of the updated -> of update

[michaelbai, 2012/04/27 23:26:04]

Done.

+  // |callback| on success.
+  //
+  // |row| is the value need to update.
+  // |selection| is the SQL WHERE clause without 'WHERE'.
+  // |selection_args| is the arguments for WHERE clause.
+  void UpdateSearchTerms(const history::SearchRow& row,
+                         const std::string& selection,
+                         const std::vector<string16>& selection_args,
+                         CancelableRequestConsumerBase* consumer,
+                         const UpdateCallback& callback);
+
+  // Deletes the matched rows and the number of deleted rows is returned from
+  // the |callback| on success.
+  // |selection| is the SQL WHERE clause without 'WHERE'.
+  // |selection_args| is the arguments for WHERE clause.
+  //
+  // if |selection| is empty all search be deleted.
+  void DeleteSearchTerms(const std::string& selection,
+                         const std::vector<string16>& selection_args,
+                         CancelableRequestConsumerBase* consumer,
+                         const DeleteCallback& callback);
+
+  // Returns the result of the given query from the |callback|.
+  // |projections| specifies the result columns, can not be empty, otherwise
+  // NULL is returned.
+  // |selection| is the SQL WHERE clause without 'WHERE'.
+  // |selection_args| is the arguments for WHERE clause.
+  // |sort_order| the SQL ORDER clause.
+  void QuerySearchTerms(
+      const std::vector<history::SearchRow::ColumnID>& projections,
+      const std::string selection,

[sky, 2012/04/27 21:37:22]

const std::string&

[michaelbai, 2012/04/27 23:26:04]

Done.

+      const std::vector<string16>& selection_args,
+      const std::string sort_order,

[sky, 2012/04/27 21:37:22]

const std::string&

[michaelbai, 2012/04/27 23:26:04]

Done.

+      CancelableRequestConsumerBase* consumer,
+      const QueryCallback& callback);
+
+ private:
+  Profile* profile_;
+
+  DISALLOW_COPY_AND_ASSIGN(AndroidHistoryProviderService);
+};
+
+#endif  // CHROME_BROWSER_HISTORY_ANDROID_ANDROID_HISTORY_PROVIDER_SERVICE_H_