Adds a method to the Performance Monitor Database to fetch the most recent metric.

chrome/browser/performance_monitor/database.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_BROWSER_PERFORMANCE_MONITOR_DATABASE_H_
 #define CHROME_BROWSER_PERFORMANCE_MONITOR_DATABASE_H_
 
 #include <vector>
 #include <set>
 #include <string>
@@ skipping 140 matching lines @@
 
   // Get the metrics that are active for the given process between |start|
   // (inclusive) and |end| (exclusive).
   std::vector<const MetricDetails*> GetActiveMetrics(const base::Time& start,
                                                      const base::Time& end);
 
   // Get the activities that are active for the given metric after |start|.
   std::vector<std::string> GetActiveActivities(MetricType metric_type,
                                                const base::Time& start);
 
+  // Populate info with the most recent activity. Return false if populate
+  // was unsuccessful.
+  bool GetRecentStatsForActivityAndMetric(const std::string& activity,
+                                          MetricType metric,
+                                          MetricInfo* info);
+
+  bool GetRecentStatsForActivityAndMetric(MetricType metric, MetricInfo* info) {
+    return GetRecentStatsForActivityAndMetric(kProcessChromeAggregate,
+                                              metric,
+                                              info);
+  }
+
   // Query given |metric_type| and |activity|.
   MetricInfoVector GetStatsForActivityAndMetric(const std::string& activity,
                                                 MetricType metric_type,
                                                 const base::Time& start,
                                                 const base::Time& end);
 
   MetricInfoVector GetStatsForActivityAndMetric(MetricType metric_type,
                                                 const base::Time& start,
                                                 const base::Time& end) {
     return GetStatsForActivityAndMetric(kProcessChromeAggregate, metric_type,
@@ skipping 86 matching lines @@
 
   leveldb::ReadOptions read_options_;
   leveldb::WriteOptions write_options_;
 
   DISALLOW_COPY_AND_ASSIGN(Database);
 };
 
 }  // namespace performance_monitor
 
 #endif  // CHROME_BROWSER_PERFORMANCE_MONITOR_DATABASE_H_