Rename 'interface' parameter

chrome/browser/power_usage_monitor/power_usage_monitor.cc

 // 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.
 
 #include "chrome/browser/power_usage_monitor/power_usage_monitor.h"
 
 #include <stddef.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 210 matching lines @@
   }
 
   if (live_renderer_ids_.empty() && previous_num_live_renderers != 0) {
     // All render processes have died.
     CancelPendingHistogramReporting();
     tracking_discharge_ = false;
   }
 }
 
 void PowerUsageMonitor::SetSystemInterfaceForTest(
-    std::unique_ptr<SystemInterface> interface) {
-  system_interface_ = std::move(interface);
+    std::unique_ptr<SystemInterface> system_interface) {
+  system_interface_ = std::move(system_interface);
 }
 
 void PowerUsageMonitor::OnPowerStateChange(bool on_battery_power) {}
 
 void PowerUsageMonitor::OnResume() {}
 
 void PowerUsageMonitor::OnSuspend() {
   CancelPendingHistogramReporting();
 }
 
 void PowerUsageMonitor::Observe(int type,
                                 const content::NotificationSource& source,
                                 const content::NotificationDetails& details) {
   content::RenderProcessHost* rph =
       content::Source<content::RenderProcessHost>(source).ptr();
   OnRenderProcessNotification(type, rph->GetID());
 }
 
 void PowerUsageMonitor::CancelPendingHistogramReporting() {
   // Cancel any in-progress histogram reports and reporting of discharge UMA.
   system_interface_->CancelPendingHistogramReports();
 }