Move InMemoryURLIndex Caching Operations to FILE Thread

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 124934)
+++ chrome/browser/history/url_index_private_data.h	(working copy)
@@ -8,8 +8,10 @@
 
 #include "base/file_path.h"
 #include "base/gtest_prod_util.h"
+#include "base/memory/scoped_ptr.h"
 #include "chrome/browser/history/in_memory_url_index_types.h"
 #include "chrome/browser/history/in_memory_url_index_cache.pb.h"
+#include "content/public/browser/notification_details.h"
 
 class HistoryQuickProviderTest;
 
@@ -22,6 +24,7 @@
 namespace imui = in_memory_url_index;
 
 class HistoryDatabase;
+class InMemoryURLIndex;
 
 // A structure describing the InMemoryURLIndex's internal data and providing for
 // restoring, rebuilding and updating that internal data.
@@ -131,23 +134,38 @@
   // down into words and each word is broken down into characters.
   void set_languages(const std::string& languages) { languages_ = languages; }
 
-  // Restores the index's private data from the cache file stored in the
-  // profile directory and returns true if successful.
-  bool RestoreFromFile(const FilePath& file_path);
+  // Creates a new URLIndexPrivateData object, populates it from the contents
+  // of the cache file stored in |file_path|, and assigns it to |data|.
+  static void RestoreFromFileTask(const FilePath& file_path,
+                                  URLIndexPrivateData* data);
 
+  // Constructs a new object by restoring its contents from the file at |path|.
+  // Returns the new URLIndexPrivateData which on success will contain the
+  // restored data but upon failure will be empty.
+  static URLIndexPrivateData* RestoreFromFile(const FilePath& 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);
 
+  // Writes |private_data| as a cache file to |file_path| and returns success
+  // via |succeeded|.
+  static void WritePrivateDataToCacheFileTask(URLIndexPrivateData* private_data,
+                                              const FilePath& file_path,
+                                              bool* succeeded);
+
   // Caches the index private data and writes the cache file to the profile
-  // directory.
+  // directory.  Called by WritePrivateDataToCacheFileTask.
   bool SaveToFile(const FilePath& file_path);
 
   // Initializes all index data members in preparation for restoring the index
   // from the cache or a complete rebuild from the history database.
   void Clear();
 
+  // Returns true if there is no data in the index.
+  bool Empty() const;
+
   // Adds |word_id| to |history_id|'s entry in the history/word map,
   // creating a new entry if one does not already exist.
   void AddToHistoryIDWordMap(HistoryID history_id, WordID word_id);
@@ -230,9 +248,6 @@
   static int ScoreComponentForMatches(const TermMatches& matches,
                                       size_t max_length);
 
-  // Determines if |gurl| has a whitelisted scheme and returns true if so.
-  bool URLSchemeIsWhitelisted(const GURL& gurl) const;
-
   // Encode a data structure into the protobuf |cache|.
   void SavePrivateData(imui::InMemoryURLIndexCacheItem* cache) const;
   void SaveWordList(imui::InMemoryURLIndexCacheItem* cache) const;
@@ -250,6 +265,9 @@
   bool RestoreWordIDHistoryMap(const imui::InMemoryURLIndexCacheItem& cache);
   bool RestoreHistoryInfoMap(const imui::InMemoryURLIndexCacheItem& cache);
 
+  // Determines if |gurl| has a whitelisted scheme and returns true if so.
+  bool URLSchemeIsWhitelisted(const GURL& gurl) const;
+
   // Cache of search terms.
   SearchTermCacheMap search_term_cache_;