Add PlayerTracker and BrowserCdm interfaces.

media/cdm/player_tracker_impl.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 "media/cdm/player_tracker_impl.h"
+
+#include <utility>
+
+#include "base/stl_util.h"
+
+namespace media {
+
+PlayerTrackerImpl::PlayerCallbacks::PlayerCallbacks(
+    base::Closure new_key_cb,
+    base::Closure cdm_unset_cb)
+    : new_key_cb(new_key_cb), cdm_unset_cb(cdm_unset_cb) {
+}
+
+PlayerTrackerImpl::PlayerCallbacks::~PlayerCallbacks() {
+}
+
+PlayerTrackerImpl::PlayerTrackerImpl() : next_registration_id_(1) {}
+
+PlayerTrackerImpl::~PlayerTrackerImpl() {}
+
+int PlayerTrackerImpl::RegisterPlayer(const base::Closure& new_key_cb,
+                                      const base::Closure& cdm_unset_cb) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  int registration_id = next_registration_id_++;
+  DCHECK(!ContainsKey(player_callbacks_map_, registration_id));
+  player_callbacks_map_.insert(std::make_pair(
+      registration_id, PlayerCallbacks(new_key_cb, cdm_unset_cb)));
+  return registration_id;
+}
+
+void PlayerTrackerImpl::UnregisterPlayer(int registration_id) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(ContainsKey(player_callbacks_map_, registration_id))
+      << registration_id;
+  player_callbacks_map_.erase(registration_id);
+}
+
+void PlayerTrackerImpl::NotifyNewKey() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  std::map<int, PlayerCallbacks>::iterator iter = player_callbacks_map_.begin();
+  for (; iter != player_callbacks_map_.end(); ++iter)
+    iter->second.new_key_cb.Run();
+}
+
+void PlayerTrackerImpl::NotifyCdmUnset() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  std::map<int, PlayerCallbacks>::iterator iter = player_callbacks_map_.begin();
+  for (; iter != player_callbacks_map_.end(); ++iter)
+    iter->second.cdm_unset_cb.Run();
+}
+
+}  // namespace media