Remove parts of //cc we aren't using

cc/base/rolling_time_delta_history.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 <cmath>
-
-#include "cc/base/rolling_time_delta_history.h"
-
-namespace cc {
-
-RollingTimeDeltaHistory::RollingTimeDeltaHistory(size_t max_size)
-    : max_size_(max_size) {}
-
-RollingTimeDeltaHistory::~RollingTimeDeltaHistory() {}
-
-void RollingTimeDeltaHistory::InsertSample(base::TimeDelta time) {
-  if (max_size_ == 0)
-    return;
-
-  if (sample_set_.size() == max_size_) {
-    sample_set_.erase(chronological_sample_deque_.front());
-    chronological_sample_deque_.pop_front();
-  }
-
-  TimeDeltaMultiset::iterator it = sample_set_.insert(time);
-  chronological_sample_deque_.push_back(it);
-}
-
-void RollingTimeDeltaHistory::Clear() {
-  chronological_sample_deque_.clear();
-  sample_set_.clear();
-}
-
-base::TimeDelta RollingTimeDeltaHistory::Percentile(double percent) const {
-  if (sample_set_.size() == 0)
-    return base::TimeDelta();
-
-  double fraction = percent / 100.0;
-
-  if (fraction <= 0.0)
-    return *(sample_set_.begin());
-
-  if (fraction >= 1.0)
-    return *(sample_set_.rbegin());
-
-  size_t num_smaller_samples =
-      static_cast<size_t>(std::ceil(fraction * sample_set_.size())) - 1;
-
-  if (num_smaller_samples > sample_set_.size() / 2) {
-    size_t num_larger_samples = sample_set_.size() - num_smaller_samples - 1;
-    TimeDeltaMultiset::const_reverse_iterator it = sample_set_.rbegin();
-    for (size_t i = 0; i < num_larger_samples; i++)
-      it++;
-    return *it;
-  }
-
-  TimeDeltaMultiset::const_iterator it = sample_set_.begin();
-  for (size_t i = 0; i < num_smaller_samples; i++)
-    it++;
-  return *it;
-}
-
-}  // namespace cc