1 files changed, 54 insertions, 0 deletions
diff --git a/content/browser/media/capture/window_activity_tracker.cc b/content/browser/media/capture/window_activity_tracker.cc
new file mode 100644
index 0000000..394792d
--- /dev/null
+++ b/content/browser/media/capture/window_activity_tracker.cc
@@ -0,0 +1,54 @@
+// Copyright 2016 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/window_activity_tracker.h"
+
+#include "base/time/time.h"
+
+namespace content {
+
+namespace {
+
+// The time period within which a triggered UI event is considered
+// currently active.
+const int kTimePeriodUiEventMicros = 100000;  // 100 ms
+
+// Minimum number of user interactions before we consider the user to be in
+// interactive mode. The goal is to prevent user interactions to launch
+// animated content from causing target playout time flip-flop.
+const int kMinUserInteractions = 5;
+
+}  // namespace
+
+WindowActivityTracker::WindowActivityTracker() {
+  Reset();
+}
+
+WindowActivityTracker::~WindowActivityTracker() {}
+
+bool WindowActivityTracker::IsUiInteractionActive() const {
+  return ui_events_count_ > kMinUserInteractions;
+}
+
+void WindowActivityTracker::RegisterMouseInteractionObserver(
+    const base::Closure& observer) {
+  mouse_interaction_observer_ = observer;
+}
+
+void WindowActivityTracker::Reset() {
+  ui_events_count_ = 0;
+  last_time_ui_event_detected_ = base::TimeTicks();
+}
+
+void WindowActivityTracker::OnMouseActivity() {
+  if (!mouse_interaction_observer_.is_null())
+    mouse_interaction_observer_.Run();
+  if (base::TimeTicks::Now() - last_time_ui_event_detected_ >
+      base::TimeDelta::FromMicroseconds(kTimePeriodUiEventMicros)) {
+    ui_events_count_++;
+  }
+  last_time_ui_event_detected_ = base::TimeTicks::Now();
+}
+
+}  // namespace content