EME: Make sure sessions are closed before they are destroyed

media/blink/webcontentdecryptionmodulesession_impl.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULESESSION_IMPL_H_
 #define MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULESESSION_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 57 matching lines @@
   scoped_refptr<CdmSessionAdapter> adapter_;
 
   // Non-owned pointer.
   Client* client_;
 
   // Session ID is the app visible ID for this session generated by the CDM.
   // This value is not set until the CDM resolves the initializeNewSession()
   // promise.
   std::string session_id_;
 
-  // Don't pass more than 1 close() event to blink::
-  // TODO(jrummell): Remove this once blink tests handle close() promise and
-  // closed() event.
+  // Keep track of whether the session has been closed or not. The session
+  // may be closed as a result of an application calling close(), or the CDM
+  // may close the session at any point.
+  // https://w3c.github.io/encrypted-media/#session-closed
+  // |has_close_been_called_| is used to keep track of whether close() has
+  // been called or not. |is_closed_| is used to keep track of whether the
+  // close event has been received or not.
+  bool has_close_been_called_;
   bool is_closed_;
 
   base::ThreadChecker thread_checker_;
   // Since promises will live until they are fired, use a weak reference when
   // creating a promise in case this class disappears before the promise
   // actually fires.
   base::WeakPtrFactory<WebContentDecryptionModuleSessionImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentDecryptionModuleSessionImpl);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULESESSION_IMPL_H_