Move ContentVideoCaptureDeviceCore from src/content to src/media

content/browser/media/capture/smooth_event_sampler.cc

Index: content/browser/media/capture/smooth_event_sampler.cc
diff --git a/content/browser/media/capture/smooth_event_sampler.cc b/content/browser/media/capture/smooth_event_sampler.cc
deleted file mode 100644
index a1638fd4e08672e65ab7307d353f0fd81f912bb4..0000000000000000000000000000000000000000
--- a/content/browser/media/capture/smooth_event_sampler.cc
+++ /dev/null
@@ -1,100 +0,0 @@
-// Copyright (c) 2015 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 "content/browser/media/capture/smooth_event_sampler.h"
-
-#include <algorithm>
-
-#include "base/trace_event/trace_event.h"
-
-namespace content {
-
-namespace {
-
-// The maximum amount of time that can elapse before considering unchanged
-// content as dirty for the purposes of timer-based overdue sampling.  This is
-// the same value found in cc::FrameRateCounter.
-const int kOverdueDirtyThresholdMillis = 250;  // 4 FPS
-
-}  // anonymous namespace
-
-SmoothEventSampler::SmoothEventSampler(base::TimeDelta min_capture_period,
-                                       int redundant_capture_goal)
-    :  redundant_capture_goal_(redundant_capture_goal),
-       overdue_sample_count_(0),
-       token_bucket_(base::TimeDelta::Max()) {
-  SetMinCapturePeriod(min_capture_period);
-}
-
-void SmoothEventSampler::SetMinCapturePeriod(base::TimeDelta period) {
-  DCHECK_GT(period, base::TimeDelta());
-  min_capture_period_ = period;
-  token_bucket_capacity_ = period + period / 2;
-  token_bucket_ = std::min(token_bucket_capacity_, token_bucket_);
-}
-
-void SmoothEventSampler::ConsiderPresentationEvent(base::TimeTicks event_time) {
-  DCHECK(!event_time.is_null());
-
-  // Add tokens to the bucket based on advancement in time.  Then, re-bound the
-  // number of tokens in the bucket.  Overflow occurs when there is too much
-  // time between events (a common case), or when RecordSample() is not being
-  // called often enough (a bug).  On the other hand, if RecordSample() is being
-  // called too often (e.g., as a reaction to IsOverdueForSamplingAt()), the
-  // bucket will underflow.
-  if (!current_event_.is_null()) {
-    if (current_event_ < event_time) {
-      token_bucket_ += event_time - current_event_;
-      if (token_bucket_ > token_bucket_capacity_)
-        token_bucket_ = token_bucket_capacity_;
-    }
-    TRACE_COUNTER1("gpu.capture",
-                   "MirroringTokenBucketUsec",
-                   std::max<int64>(0, token_bucket_.InMicroseconds()));
-  }
-  current_event_ = event_time;
-}
-
-bool SmoothEventSampler::ShouldSample() const {
-  return token_bucket_ >= min_capture_period_;
-}
-
-void SmoothEventSampler::RecordSample() {
-  token_bucket_ -= min_capture_period_;
-  if (token_bucket_ < base::TimeDelta())
-    token_bucket_ = base::TimeDelta();
-  TRACE_COUNTER1("gpu.capture",
-                 "MirroringTokenBucketUsec",
-                 std::max<int64>(0, token_bucket_.InMicroseconds()));
-
-  if (HasUnrecordedEvent()) {
-    last_sample_ = current_event_;
-    overdue_sample_count_ = 0;
-  } else {
-    ++overdue_sample_count_;
-  }
-}
-
-bool SmoothEventSampler::IsOverdueForSamplingAt(base::TimeTicks event_time)
-    const {
-  DCHECK(!event_time.is_null());
-
-  if (!HasUnrecordedEvent() && overdue_sample_count_ >= redundant_capture_goal_)
-    return false;  // Not dirty.
-
-  if (last_sample_.is_null())
-    return true;
-
-  // If we're dirty but not yet old, then we've recently gotten updates, so we
-  // won't request a sample just yet.
-  base::TimeDelta dirty_interval = event_time - last_sample_;
-  return dirty_interval >=
-      base::TimeDelta::FromMilliseconds(kOverdueDirtyThresholdMillis);
-}
-
-bool SmoothEventSampler::HasUnrecordedEvent() const {
-  return !current_event_.is_null() && current_event_ != last_sample_;
-}
-
-}  // namespace content