[Fuchsia][EME] Enable Widevine

1. Turn on flag 'enable_widevine' and
'ENABLE_PROTECTED_MEDIA_IDENTIFIER_PERMISSION'.

2. Add widevine key system config.

Bug: 991723
Test: Shaka player demo "Dig the Uke".
Change-Id: I49a7661fb4b8b5732b597622f9d496ea611dc9ef
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1783802
Commit-Queue: Yuchen Liu <yucliu@chromium.org>
Reviewed-by: Sergey Ulanov <sergeyu@chromium.org>
Reviewed-by: Xiaohan Wang <xhwang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#694945}

content/browser/BUILD.gn

@@ -1994,7 +1994,7 @@ jumbo_source_set("browser") {
     ]
   }
 
-  if (is_chromeos || is_android || is_chromecast) {
+  if (is_chromeos || is_android || is_chromecast || is_fuchsia) {
     defines += [ "ENABLE_PROTECTED_MEDIA_IDENTIFIER_PERMISSION" ]
   }
 

fuchsia/engine/BUILD.gn

@@ -67,6 +67,7 @@ component("web_engine_core") {
     ":web_engine_pak",
     "//base",
     "//base:base_static",
+    "//components/cdm/renderer",
     "//components/version_info",
     "//content/public/app:both",
     "//content/public/browser",

fuchsia/engine/renderer/DEPS

 include_rules = [
+  "+components/cdm/renderer",
   "+content/public/renderer",
+  "+media",
   "+mojo/public/cpp/bindings",
   "+services/service_manager/public/cpp",
   "+third_party/blink/public/common/associated_interfaces",
+  "+third_party/widevine/cdm/widevine_cdm_common.h",
 ]

fuchsia/engine/renderer/web_engine_content_renderer_client.cc

@@ -5,10 +5,13 @@
 #include "fuchsia/engine/renderer/web_engine_content_renderer_client.h"
 
 #include "base/macros.h"
+#include "components/cdm/renderer/widevine_key_system_properties.h"
 #include "content/public/renderer/render_frame.h"
 #include "fuchsia/engine/renderer/on_load_script_injector.h"
+#include "media/base/eme_constants.h"
 #include "services/service_manager/public/cpp/binder_registry.h"
 #include "third_party/blink/public/common/associated_interfaces/associated_interface_registry.h"
+#include "third_party/widevine/cdm/widevine_cdm_common.h"
 
 WebEngineContentRendererClient::WebEngineContentRendererClient() = default;
 
@@ -20,3 +23,31 @@ void WebEngineContentRendererClient::RenderFrameCreated(
   // The objects' lifetimes are bound to the RenderFrame's lifetime.
   new OnLoadScriptInjector(render_frame);
 }
+
+void WebEngineContentRendererClient::AddSupportedKeySystems(
+    std::vector<std::unique_ptr<media::KeySystemProperties>>* key_systems) {
+  // TODO(yucliu): Check if Widevine is enabled from command line/context
+  // feature flags.
+  // TODO(yucliu): Check supported hw video decoders.
+  media::SupportedCodecs supported_video_codecs = media::EME_CODEC_NONE;
+
+  base::flat_set<media::EncryptionMode> encryption_schemes{
+      media::EncryptionMode::kCenc, media::EncryptionMode::kCbcs};
+
+  // Fuchsia always decrypts audio into clear buffers and return them back to
+  // Chromium. Hardware secured decoders are only available for supported
+  // video codecs.
+  key_systems->emplace_back(new cdm::WidevineKeySystemProperties(
+      media::EME_CODEC_AUDIO_ALL | supported_video_codecs,  // codecs
+      encryption_schemes,      // encryption schemes
+      supported_video_codecs,  // hw secure codecs
+      encryption_schemes,      // hw secure encryption schemes
+      cdm::WidevineKeySystemProperties::Robustness::
+          HW_SECURE_CRYPTO,  // max audio robustness
+      cdm::WidevineKeySystemProperties::Robustness::
+          HW_SECURE_ALL,                            // max video robustness
+      media::EmeSessionTypeSupport::NOT_SUPPORTED,  // persistent license
+      media::EmeSessionTypeSupport::NOT_SUPPORTED,  // persistent usage record
+      media::EmeFeatureSupport::ALWAYS_ENABLED,     // persistent state
+      media::EmeFeatureSupport::ALWAYS_ENABLED));   // distinctive identifier
+}

fuchsia/engine/renderer/web_engine_content_renderer_client.h

@@ -15,6 +15,9 @@ class WebEngineContentRendererClient : public content::ContentRendererClient {
 
   // content::ContentRendererClient overrides.
   void RenderFrameCreated(content::RenderFrame* render_frame) override;
+  void AddSupportedKeySystems(
+      std::vector<std::unique_ptr<media::KeySystemProperties>>* key_systems)
+      override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WebEngineContentRendererClient);

third_party/widevine/cdm/widevine.gni

@@ -6,11 +6,11 @@ import("//build/config/chrome_build.gni")
 import("//media/media_options.gni")
 
 declare_args() {
-  # Enables Widevine key system support. Enabled by default in Google Chrome and
-  # on Android.
+  # Enables Widevine key system support. Enabled by default in Google Chrome,
+  # on Android and Fuchsia platforms.
   # Can be optionally enabled in Chromium on non-Android platforms. Please see
   # //src/third_party/widevine/LICENSE file for details.
-  enable_widevine = is_chrome_branded || is_android
+  enable_widevine = is_chrome_branded || is_android || is_fuchsia
 }
 
 # Widevine CDM is available as a library CDM on the following platforms and