Don't restore DRM keys before releasing them

PiperOrigin-RevId: 375436117

RELEASENOTES.md

@@ -12,6 +12,9 @@
 *   HLS
     *   Fix a bug where skipping into spliced-in chunks triggered an assertion
         error ([#8937](https://github.com/google/ExoPlayer/issues/8937).
+*   DRM:
+    *   Don't restore offline keys before releasing them. In OEMCrypto v16+ keys
+        must be released without restoring them first.
 
 ### 2.14.0 (2021-05-13)
 

library/core/src/main/java/com/google/android/exoplayer2/drm/DefaultDrmSession.java

@@ -430,11 +430,7 @@ import org.checkerframework.checker.nullness.qual.RequiresNonNull;
       case DefaultDrmSessionManager.MODE_RELEASE:
         Assertions.checkNotNull(offlineLicenseKeySetId);
         Assertions.checkNotNull(this.sessionId);
-        // It's not necessary to restore the key before releasing it but this serves as a good
-        // fast-failure check.
-        if (restoreKeys()) {
-          postKeyRequest(offlineLicenseKeySetId, ExoMediaDrm.KEY_TYPE_RELEASE, allowRetry);
-        }
+        postKeyRequest(offlineLicenseKeySetId, ExoMediaDrm.KEY_TYPE_RELEASE, allowRetry);
         break;
       default:
         break;