Move InMemoryURLIndex Caching Operations to FILE Thread

chrome/browser/history/history_backend_unittest.cc

Index: chrome/browser/history/history_backend_unittest.cc
===================================================================
--- chrome/browser/history/history_backend_unittest.cc	(revision 117518)
+++ chrome/browser/history/history_backend_unittest.cc	(working copy)
@@ -146,7 +146,6 @@
 
   BookmarkModel bookmark_model_;
 
- protected:
   bool loaded_;
 
  private:
@@ -157,7 +156,8 @@
     if (!file_util::CreateNewTempDirectory(FILE_PATH_LITERAL("BackendTest"),
                                            &test_dir_))
       return;
-    backend_ = new HistoryBackend(test_dir_,
+    backend_ = new HistoryBackend(NULL,
+                                  test_dir_,
                                   0,
                                   new HistoryBackendTestDelegate(this),
                                   &bookmark_model_);
@@ -955,7 +955,8 @@
   FilePath new_history_file = new_history_path.Append(chrome::kHistoryFilename);
   ASSERT_TRUE(file_util::CopyFile(old_history_path, new_history_file));
 
-  backend_ = new HistoryBackend(new_history_path,
+  backend_ = new HistoryBackend(NULL,
+                                new_history_path,
                                 0,
                                 new HistoryBackendTestDelegate(this),
                                 &bookmark_model_);