Move Ownership of IMUI to HistoryService.

chrome/browser/history/url_index_private_data.h

Index: chrome/browser/history/url_index_private_data.h
===================================================================
--- chrome/browser/history/url_index_private_data.h	(revision 120346)
+++ chrome/browser/history/url_index_private_data.h	(working copy)
@@ -19,6 +19,8 @@
 
 namespace imui = in_memory_url_index;
 
+class HistoryDatabase;
+
 // A structure describing the InMemoryURLIndex's internal data and providing for
 // restoring, rebuilding and updating that internal data.
 class URLIndexPrivateData {
@@ -130,13 +132,15 @@
   // profile directory and returns true if successful.
   bool RestoreFromFile(const FilePath& file_path);
 
+  // Constructs a new object by rebuilding its contents from the history
+  // database in |history_db|. Returns the new URLIndexPrivateData which on
+  // success will contain the rebuilt data but upon failure will be empty.
+  static URLIndexPrivateData* RebuildFromHistory(HistoryDatabase* history_db);
+
   // Caches the index private data and writes the cache file to the profile
   // directory.
   bool SaveToFile(const FilePath& file_path);
 
-  // Reloads the history index from |history_db|.
-  bool ReloadFromHistory(URLDatabase* history_db);
-
   // Initializes all index data members in preparation for restoring the index
   // from the cache or a complete rebuild from the history database.
   void Clear();
@@ -153,17 +157,22 @@
 
   // URL History indexing support functions.
 
-  // Indexes one URL history item.
-  void IndexRow(const URLRow& row);
+  // Indexes one URL history item as described by |row|. Returns true if the
+  // row was actually indexed.
+  bool IndexRow(const URLRow& row);
 
-  // Updates or adds an history item to the index if it meets the minimum
-  // 'quick' criteria.
-  void UpdateURL(URLID row_id, const URLRow& row);
+  // Adds the history item in |row| to the index if it does not already already
+  // exist and it meets the minimum 'quick' criteria. If the row already exists
+  // in the index then the index will be updated if the row still meets the
+  // criteria, otherwise the row will be removed from the index. Returns true
+  // if the index was actually updated.
+  bool UpdateURL(const URLRow& row);
 
-  // Deletes indexing data for an history item. The item may not have actually
-  // been indexed (which is the case if it did not previously meet minimum
-  // 'quick' criteria).
-  void DeleteURL(URLID row_id);
+  // Deletes indexing data for the history item with the URL given in |url|.
+  // The item may not have actually been indexed, which is the case if it did
+  // not previously meet minimum 'quick' criteria. Returns true if the index
+  // was actually updated.
+  bool DeleteURL(const GURL& url);
 
   // Parses and indexes the words in the URL and page title of |row|.
   void AddRowWordsToIndex(const URLRow& row);