[Chromecast] Pass security origin to CastCdm and remove destination url

1. Pass security origin when creating CastCdm.
2. Remove destination url in media session message callback, as
unprefixed eme doesn't need it.

BUG=internal b/30075657
TEST=Mpl End2End test.

Review-Url: https://codereview.chromium.org/2160953004
Cr-Commit-Position: refs/heads/master@{#407522}

chromecast/browser/media/cast_browser_cdm_factory.cc

@@ -53,7 +53,7 @@ void CastBrowserCdmFactory::Create(
   if (cast_key_system == chromecast::media::KEY_SYSTEM_CLEAR_KEY) {
     // TODO(gunsch): handle ClearKey decryption. See crbug.com/441957
   } else {
-    cast_cdm = CreatePlatformBrowserCdm(cast_key_system);
+    cast_cdm = CreatePlatformBrowserCdm(cast_key_system, security_origin);
   }
 
   if (!cast_cdm) {
@@ -81,7 +81,8 @@ void CastBrowserCdmFactory::Create(
 }
 
 scoped_refptr<CastCdm> CastBrowserCdmFactory::CreatePlatformBrowserCdm(
-    const CastKeySystem& cast_key_system) {
+    const CastKeySystem& cast_key_system,
+    const GURL& security_origin) {
   return nullptr;
 }
 

chromecast/browser/media/cast_browser_cdm_factory.h

@@ -41,7 +41,8 @@ class CastBrowserCdmFactory : public ::media::CdmFactory {
 
   // Provides a platform-specific BrowserCdm instance.
   virtual scoped_refptr<CastCdm> CreatePlatformBrowserCdm(
-      const CastKeySystem& cast_key_system);
+      const CastKeySystem& cast_key_system,
+      const GURL& security_origin);
 
  protected:
   MediaResourceTracker* media_resource_tracker_;

chromecast/media/cdm/BUILD.gn

@@ -23,6 +23,7 @@ source_set("cdm") {
     "//base",
     "//chromecast/media/base",
     "//media",
+    "//url:url",
   ]
 
   if (is_android && use_playready) {

chromecast/media/cdm/cast_cdm.cc

@@ -16,6 +16,7 @@
 #include "media/base/cdm_key_information.h"
 #include "media/base/decryptor.h"
 #include "media/cdm/player_tracker_impl.h"
+#include "url/gurl.h"
 
 namespace chromecast {
 namespace media {
@@ -109,9 +110,8 @@ void CastCdm::UnregisterPlayer(int registration_id) {
 
 void CastCdm::OnSessionMessage(const std::string& session_id,
                                const std::vector<uint8_t>& message,
-                               const GURL& destination_url,
                                ::media::MediaKeys::MessageType message_type) {
-  session_message_cb_.Run(session_id, message_type, message, destination_url);
+  session_message_cb_.Run(session_id, message_type, message, GURL::EmptyGURL());
 }
 
 void CastCdm::OnSessionClosed(const std::string& session_id) {

chromecast/media/cdm/cast_cdm.h

@@ -77,7 +77,6 @@ class CastCdm : public ::media::MediaKeys {
 
   void OnSessionMessage(const std::string& session_id,
                         const std::vector<uint8_t>& message,
-                        const GURL& destination_url,
                         ::media::MediaKeys::MessageType message_type);
   void OnSessionClosed(const std::string& session_id);
   void OnSessionKeysChange(const std::string& session_id,