Send UMA stability stats in a separate UMA log on startup.

chrome/common/metrics/metrics_log_manager.h

 // 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_COMMON_METRICS_METRICS_LOG_MANAGER_H_
 #define CHROME_COMMON_METRICS_METRICS_LOG_MANAGER_H_
 
 
 #include <string>
 #include <vector>
@@ skipping 154 matching lines @@
   // |max_ongoing_log_store_size_|).
   // NOTE: This clears the contents of |log| (to avoid an expensive copy),
   // so the log should be discarded after this call.
   void StoreLog(SerializedLog* log,
                 LogType log_type,
                 StoreType store_type);
 
   // Compresses |current_log_| into |compressed_log|.
   void CompressCurrentLog(SerializedLog* compressed_log);
 
+  // Tracks whether unsent logs (if any) have been loaded from the serializer.
+  bool unsent_logs_loaded_;
+
   // The log that we are still appending to.
   scoped_ptr<MetricsLogBase> current_log_;
   LogType current_log_type_;
 
   // A paused, previously-current log.
   scoped_ptr<MetricsLogBase> paused_log_;
   LogType paused_log_type_;
 
   // Helper class to handle serialization/deserialization of logs for persistent
   // storage. May be NULL.
@@ skipping 17 matching lines @@
   // This is necessary because during an upload there are two logs (staged
   // and current) and a client might store them in either order, so it's
   // not necessarily the case that the provisional store is the last store.
   int last_provisional_store_index_;
   LogType last_provisional_store_type_;
 
   DISALLOW_COPY_AND_ASSIGN(MetricsLogManager);
 };
 
 #endif  // CHROME_COMMON_METRICS_METRICS_LOG_MANAGER_H_