Implement checks for distinctiveIdentifier and persistentState in requestMediaKeySystemAccess().

components/cdm/renderer/android_key_systems.cc

Index: components/cdm/renderer/android_key_systems.cc
diff --git a/components/cdm/renderer/android_key_systems.cc b/components/cdm/renderer/android_key_systems.cc
index 83a0d0481df831e62aa1727d3dfaf23a08efcb4a..c8c71ee66f8c41828a4958538a0cc1012c5d51b7 100644
--- a/components/cdm/renderer/android_key_systems.cc
+++ b/components/cdm/renderer/android_key_systems.cc
@@ -75,6 +75,8 @@ void AddAndroidPlatformKeySystems(
       if (response.compositing_codecs & media::EME_CODEC_MP4_ALL)
         info.supported_init_data_types |= media::EME_INIT_DATA_TYPE_CENC;
 #endif  // defined(USE_PROPRIETARY_CODECS)
+      // Prevent creation thorugh the requestMediaKeySystemAccess() API.

[jrummell, 2015/02/14 01:28:35]

s/thorugh/through/

[ddorwin, 2015/02/17 20:56:46]

Until https://github.com/w3c/encrypted-media/issues/29 is implemented, this does
not actually affect requestMediaKeySystemAccess(), right?

Is the goal to prevent use of platform key systems with unprefixed EME? If so,
maybe we should be clearer about this or handle it differently. Let's discuss.

[sandersd (OOO until July 31), 2015/02/18 23:41:17]

Previously there was a specific check for this, but it's been removed in this
patch set. Is there something more we should be doing? (I'm assuming it's not
necessary since you are disabling unprefixed on the relevant platforms.)

[sandersd (OOO until July 31), 2015/02/18 23:41:17]

Done.

+      info.supported_session_types = media::EME_SESSION_TYPE_NONE;
       concrete_key_systems->push_back(info);
     }
   }