Media Remoting: Add remoting control logic for encrypted contents.

media/remoting/remoting_cdm_factory.cc

+// 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 "media/remoting/remoting_cdm_factory.h"
+
+#include "base/bind.h"
+#include "base/single_thread_task_runner.h"
+#include "media/base/cdm_config.h"
+#include "media/remoting/remoting_cdm.h"
+
+namespace media {
+
+RemotingCdmFactory::RemotingCdmFactory(
+    std::unique_ptr<CdmFactory> default_cdm_factory,
+    mojom::RemoterFactory* remoter_factory,
+    RemotingSinkObserver* sink_observer)
+    : default_cdm_factory_(std::move(default_cdm_factory)),
+      remoter_factory_(remoter_factory),
+      sink_observer_(sink_observer),
+      weak_factory_(this) {
+  DCHECK(default_cdm_factory_);
+  DCHECK(remoter_factory_);
+  DCHECK(sink_observer_);
+}
+
+RemotingCdmFactory::~RemotingCdmFactory() {}
+
+std::unique_ptr<RemotingCdmController>
+RemotingCdmFactory::CreateRemotingCdmController() {
+  mojom::RemotingSourcePtr remoting_source;
+  mojom::RemotingSourceRequest remoting_source_request =
+      mojo::GetProxy(&remoting_source);
+  mojom::RemoterPtr remoter;
+  remoter_factory_->Create(std::move(remoting_source),
+                           mojo::GetProxy(&remoter));
+  scoped_refptr<RemotingSourceImpl> remoting_source_impl =
+      new RemotingSourceImpl(std::move(remoting_source_request),
+                             std::move(remoter));
+  // Initialize the sink availability according to |sink_observer_|.

[miu, 2016/11/05 04:05:15]

Please add to this comment: Explain that we are purposely copying the
"available" state before the RemotingCdmController would naturally get the
notification. Also, explain why we are doing this. (Pretend someone unfamiliar
with this project will read this code 2+ years from now.)

You might even want to start the comment with "HACK":

  // HACK: Copy-over the sink availability status from |sink_observer_| ...and
why...

[xjz, 2016/11/07 19:03:55]

Done.

+  if (sink_observer_->is_sink_available())
+    remoting_source_impl->OnSinkAvailable();
+  return base::MakeUnique<RemotingCdmController>(remoting_source_impl);
+}
+
+// TODO(xjz): Replace the callbacks with an interface. http://crbug.com/657940.
+void RemotingCdmFactory::Create(
+    const std::string& key_system,
+    const GURL& security_origin,
+    const CdmConfig& cdm_config,
+    const SessionMessageCB& session_message_cb,
+    const SessionClosedCB& session_closed_cb,
+    const SessionKeysChangeCB& session_keys_change_cb,
+    const SessionExpirationUpdateCB& session_expiration_update_cb,
+    const CdmCreatedCB& cdm_created_cb) {
+  std::unique_ptr<RemotingCdmController> remoting_cdm_controller =
+      CreateRemotingCdmController();
+  // Get the raw pointer of |remoting_cdm_controller| as it will be invalidated
+  // before calling |ShouldCreateRemotingCdm()| by base::Passed().
+  RemotingCdmController* remoting_cdm_controller_ptr =
+      remoting_cdm_controller.get();
+  remoting_cdm_controller_ptr->ShouldCreateRemotingCdm(base::Bind(

[xhwang, 2016/11/05 02:39:58]

Can we check sink_observer_->is_sink_available() here and if it's false then
call CreateCdm() directly? Or add a comment that if sink is not available we'll
call CreateCdm() immediately.

[miu, 2016/11/05 04:05:15]

+1

[xjz, 2016/11/07 19:03:55]

Done.

[xjz, 2016/11/07 19:03:55]

Done.

+      &RemotingCdmFactory::CreateCdm, weak_factory_.GetWeakPtr(), key_system,
+      security_origin, cdm_config, session_message_cb, session_closed_cb,
+      session_keys_change_cb, session_expiration_update_cb, cdm_created_cb,
+      base::Passed(&remoting_cdm_controller)));
+}
+
+void RemotingCdmFactory::CreateCdm(
+    const std::string& key_system,
+    const GURL& security_origin,
+    const CdmConfig& cdm_config,
+    const SessionMessageCB& session_message_cb,
+    const SessionClosedCB& session_closed_cb,
+    const SessionKeysChangeCB& session_keys_change_cb,
+    const SessionExpirationUpdateCB& session_expiration_update_cb,
+    const CdmCreatedCB& cdm_created_cb,
+    std::unique_ptr<RemotingCdmController> remoting_cdm_controller,
+    bool is_remoting) {
+  if (is_remoting) {
+    VLOG(1) << "Create remoting CDM.";
+    // TODO(xjz): Merge this with erickung's implementation to create remoting
+    // CDM.
+    NOTIMPLEMENTED();
+  } else {
+    VLOG(1) << "Create default CDM.";
+    default_cdm_factory_->Create(key_system, security_origin, cdm_config,
+                                 session_message_cb, session_closed_cb,
+                                 session_keys_change_cb,
+                                 session_expiration_update_cb, cdm_created_cb);
+  }
+}
+
+}  // namespace media