system_wrappers: Fix include header guards.

webrtc/system_wrappers/include/metrics.h

 //
 // Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the LICENSE file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS.  All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 //
 
-#ifndef WEBRTC_SYSTEM_WRAPPERS_INTERFACE_METRICS_H_
-#define WEBRTC_SYSTEM_WRAPPERS_INTERFACE_METRICS_H_
+#ifndef WEBRTC_SYSTEM_WRAPPERS_INCLUDE_METRICS_H_
+#define WEBRTC_SYSTEM_WRAPPERS_INCLUDE_METRICS_H_
 
 #include <string>
 
 #include "webrtc/common_types.h"
 
 // Macros for allowing WebRTC clients (e.g. Chrome) to gather and aggregate
 // statistics.
 //
 // Histogram for counters.
 // RTC_HISTOGRAM_COUNTS(name, sample, min, max, bucket_count);
@@ skipping 105 matching lines @@
     const std::string& name, int boundary);
 
 // Function for adding a |sample| to a histogram.
 // |name| can be used to verify that it matches the histogram name.
 void HistogramAdd(
     Histogram* histogram_pointer, const std::string& name, int sample);
 
 }  // namespace metrics
 }  // namespace webrtc
 
-#endif  // WEBRTC_SYSTEM_WRAPPERS_INTERFACE_METRICS_H_
+#endif  // WEBRTC_SYSTEM_WRAPPERS_INCLUDE_METRICS_H_