Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

modules/video_coding/utility/moving_average.h

@@ -0,0 +1,35 @@
+/*
+ *  Copyright (c) 2015 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_MODULES_VIDEO_CODING_UTILITY_MOVING_AVERAGE_H_
+#define WEBRTC_MODULES_VIDEO_CODING_UTILITY_MOVING_AVERAGE_H_
+
+#include <vector>
+
+#include "webrtc/api/optional.h"
+
+namespace webrtc {
+class MovingAverage {
+ public:
+  explicit MovingAverage(size_t s);
+  void AddSample(int sample);
+  rtc::Optional<int> GetAverage() const;
+  rtc::Optional<int> GetAverage(size_t num_samples) const;
+  void Reset();
+  size_t size() const;
+
+ private:
+  size_t count_ = 0;
+  int sum_ = 0;
+  std::vector<int> sum_history_;
+};
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_VIDEO_CODING_UTILITY_MOVING_AVERAGE_H_