Improve profile stats performace.

chrome/browser/profiles/profile_statistics_aggregator.h

 // Copyright 2016 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_PROFILES_PROFILE_STATISTICS_AGGREGATOR_H_
 #define CHROME_BROWSER_PROFILES_PROFILE_STATISTICS_AGGREGATOR_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 32 matching lines @@
   void AddCallbackAndStartAggregator(
       const profiles::ProfileStatisticsCallback& stats_callback);
 
   // The method below is used for testing.
   size_t GetCallbackCount();
 
  private:
   friend class base::RefCountedThreadSafe<ProfileStatisticsAggregator>;
 
   struct ProfileStatValue {
-    int count;
-    bool success;  // false means the statistics failed to load
+    int count = 0;
+    bool success = false;  // False means the statistics failed to load.
   };
 
   ~ProfileStatisticsAggregator();
 
   // Start gathering statistics. Also cancels existing statistics tasks.
   void StartAggregator();
 
   // Callback functions
   // Normal callback. Appends result to |profile_category_stats_|, and then call
   // the external callback. All other callbacks call this function.
@@ skipping 85 matching lines @@
   // Bookmark counting
   std::unique_ptr<BookmarkModelHelper> bookmark_model_helper_;
 
   // Password counting.
   PasswordStoreConsumerHelper password_store_consumer_helper_;
 
   DISALLOW_COPY_AND_ASSIGN(ProfileStatisticsAggregator);
 };
 
 #endif  // CHROME_BROWSER_PROFILES_PROFILE_STATISTICS_AGGREGATOR_H_