media: Refactor MediaCrypto creation and notification.

media/base/android/media_codec_player.cc

Index: media/base/android/media_codec_player.cc
diff --git a/media/base/android/media_codec_player.cc b/media/base/android/media_codec_player.cc
index a58ac27b6e52bce5fbf0fc082b537d008a55bee2..1fb821d3b759d55609fd3ad3eb374ac6799d6a9a 100644
--- a/media/base/android/media_codec_player.cc
+++ b/media/base/android/media_codec_player.cc
@@ -937,7 +937,15 @@ void MediaCodecPlayer::OnMediaCryptoReady(
   // and the surface requirement does not change until new SetCdm() is called.
 
   DCHECK(media_crypto);
-  DCHECK(!media_crypto->is_null());
+
+  if (media_crypto->is_null()) {
+    // TODO(timav): Fail playback nicely here if needed. Note that we could get
+    // here even though the stream to play is unencrypted and therefore
+    // MediaCrypto is not needed. In that case, we may ignore this error and
+    // continue playback, or fail the playback.
+    LOG(ERROR) << "MediaCrypto creation failed.";
+    return;
+  }
 
   media_crypto_ = media_crypto.Pass();