[Chromecast] Add a custom CastMediaClient for Chromecast

chromecast/common/media/cast_media_client.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.
+
+// TODO(servolk): Is there a better way to override just IsSupportedVideoConfig
+// without duplicating content::RenderMediaClient implementation?
+// For now define MEDIA_IMPLEMENTATION to be able to access the default media
+// client via ::media::GetMediaClient.
+#define MEDIA_IMPLEMENTATION

[halliwell, 2016/07/27 14:23:17]

does this break component build?

Also, it's a pre-existing problem, but it definitely seems quite ugly how
RenderMediaClient gets instantiated :(

Could we subclass RenderMediaClient?
Also, I wonder if ContentRendererClient could have API for instantiating the
MediaClient instance instead of RenderThreadImpl being hardcoded to call
RenderMediaClient::Initialize?  Then the correct client object could be
instantiated once and set.

[servolk, 2016/07/27 18:56:34]

The most recent trybot runs were all green, including cast_shell trybots, so I
think it shouldn't break the build. But to be extra safe we could just duplicate
the media::GetMediaClient definition here instead of defining
MEDIA_IMPLEMENTATION.
The RenderMediaClient unfortunately is not easy subclass - it's internal to
content/ and that's enforced by DEPS checks. I'll try following up with content
/ media folks about this. But I think it will take some time. In the meantime
this solution should unblock us for 1.21.

[halliwell, 2016/07/27 19:58:48]

There is no chromium trybot for component build of cast_shell.  slan@ sent an
email with instructions on how to build it.
Ah yes, was forgetting it's not in content 'public'.  I agree this solution is
fine for unblocking, but would be good to follow up on something cleaner
afterwards.

[servolk, 2016/07/27 21:11:38]

Ok, I'll try a component build locally.

+
+#include "chromecast/common/media/cast_media_client.h"
+
+#include "base/lazy_instance.h"
+#include "chromecast/media/base/media_codec_support.h"
+#include "chromecast/public/media_codec_support_shlib.h"
+
+namespace chromecast {
+namespace media {
+
+static base::LazyInstance<CastMediaClient>::Leaky g_cast_media_client =
+    LAZY_INSTANCE_INITIALIZER;
+
+void CastMediaClient::Initialize() {
+  g_cast_media_client.Get();
+}
+
+CastMediaClient::CastMediaClient() {
+  content_media_client_ = ::media::GetMediaClient();
+  // Ensure that CastMediaClient gets initialized after the
+  // content::RenderMediaClient.
+  DCHECK(content_media_client_);
+  ::media::SetMediaClient(this);
+}
+
+CastMediaClient::~CastMediaClient() {}
+
+void CastMediaClient::AddKeySystemsInfoForUMA(
+    std::vector<::media::KeySystemInfoForUMA>* key_systems_info_for_uma) {
+  content_media_client_->AddKeySystemsInfoForUMA(key_systems_info_for_uma);
+}
+
+bool CastMediaClient::IsKeySystemsUpdateNeeded() {
+  return content_media_client_->IsKeySystemsUpdateNeeded();
+}
+
+void CastMediaClient::AddSupportedKeySystems(
+    std::vector<std::unique_ptr<::media::KeySystemProperties>>*
+        key_systems_properties) {
+  content_media_client_->AddSupportedKeySystems(key_systems_properties);
+}
+
+void CastMediaClient::RecordRapporURL(const std::string& metric,
+                                      const GURL& url) {
+  content_media_client_->RecordRapporURL(metric, url);
+}
+
+// static
+bool CastMediaClient::IsSupportedVideoConfig(::media::VideoCodec codec,
+                                             ::media::VideoCodecProfile profile,
+                                             int level) {
+  if (MediaCapabilitiesShlib::IsSupportedVideoConfig) {
+    return MediaCapabilitiesShlib::IsSupportedVideoConfig(
+        ToCastVideoCodec(codec), ToCastVideoProfile(profile), level);
+  }
+  LOG(WARNING) << __FUNCTION__
+               << " using default MediaClient::IsSupportedVideoConfig";
+  return content_media_client_->IsSupportedVideoConfig(codec, profile, level);
+}
+
+}  // namespace media
+}  // namespace chromecast