Rename 'interface' parameter

chrome/browser/power_usage_monitor/power_usage_monitor.h

 // Copyright 2014 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_POWER_USAGE_MONITOR_POWER_USAGE_MONITOR_H_
 #define CHROME_BROWSER_POWER_USAGE_MONITOR_POWER_USAGE_MONITOR_H_
 
 #include "base/containers/hash_tables.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
@@ skipping 43 matching lines @@
 
   double discharge_amount() const {
     return initial_battery_level_ - current_battery_level_;
   }
 
   // Start monitoring power usage.
   // Note that the actual monitoring will be delayed until 30 minutes after
   // system boot.
   void Start();
 
-  void SetSystemInterfaceForTest(std::unique_ptr<SystemInterface> interface);
+  void SetSystemInterfaceForTest(
+      std::unique_ptr<SystemInterface> system_interface);
 
   // Overridden from base::PowerObserver:
   void OnPowerStateChange(bool on_battery_power) override;
   void OnResume() override;
   void OnSuspend() override;
 
   // Overridden from NotificationObserver:
   void Observe(int type,
                const content::NotificationSource& source,
                const content::NotificationDetails& details) override;
@@ skipping 45 matching lines @@
   base::Time start_discharge_time_;
 
   // IDs of live renderer processes.
   base::hash_set<int> live_renderer_ids_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(PowerUsageMonitor);
 };
 
 #endif  // CHROME_BROWSER_POWER_USAGE_MONITOR_POWER_USAGE_MONITOR_H_