Revert of Reland "Move smoothing filter to common audio".

webrtc/base/analytics/exp_filter.cc

Index: webrtc/base/analytics/exp_filter.cc
diff --git a/webrtc/base/analytics/exp_filter.cc b/webrtc/base/analytics/exp_filter.cc
deleted file mode 100644
index 48fe1ad97a906ba5f9a4f69cf1074e11b7c82409..0000000000000000000000000000000000000000
--- a/webrtc/base/analytics/exp_filter.cc
+++ /dev/null
@@ -1,43 +0,0 @@
-/*
- *  Copyright (c) 2011 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.
- */
-
-#include "webrtc/base/analytics/exp_filter.h"
-
-#include <math.h>
-
-namespace rtc {
-
-const float ExpFilter::kValueUndefined = -1.0f;
-
-void ExpFilter::Reset(float alpha) {
-  alpha_ = alpha;
-  filtered_ = kValueUndefined;
-}
-
-float ExpFilter::Apply(float exp, float sample) {
-  if (filtered_ == kValueUndefined) {
-    // Initialize filtered value.
-    filtered_ = sample;
-  } else if (exp == 1.0) {
-    filtered_ = alpha_ * filtered_ + (1 - alpha_) * sample;
-  } else {
-    float alpha = pow(alpha_, exp);
-    filtered_ = alpha * filtered_ + (1 - alpha) * sample;
-  }
-  if (max_ != kValueUndefined && filtered_ > max_) {
-    filtered_ = max_;
-  }
-  return filtered_;
-}
-
-void ExpFilter::UpdateBase(float alpha) {
-  alpha_ = alpha;
-}
-}  // namespace rtc