Keep reference to CDM to avoid it's premature destruction

media/blink/webcontentdecryptionmodule_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_WEBCONTENTDECRYPTIONMODULE_IMPL_H_
 #define MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULE_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/strings/string16.h"
 #include "media/blink/media_blink_export.h"
 #include "third_party/WebKit/public/platform/WebContentDecryptionModule.h"
 #include "third_party/WebKit/public/platform/WebContentDecryptionModuleResult.h"
 
 namespace blink {
 #if defined(ENABLE_PEPPER_CDMS)
 class WebLocalFrame;
 #endif
 class WebSecurityOrigin;
 }
 
 namespace media {
 
 struct CdmConfig;
-class CdmContext;
 class CdmFactory;
 class CdmSessionAdapter;
+class MediaKeys;
 class WebContentDecryptionModuleSessionImpl;
 
 class MEDIA_BLINK_EXPORT WebContentDecryptionModuleImpl
     : public blink::WebContentDecryptionModule {
  public:
   static void Create(
       CdmFactory* cdm_factory,
       const base::string16& key_system,
       const blink::WebSecurityOrigin& security_origin,
       const CdmConfig& cdm_config,
       std::unique_ptr<blink::WebContentDecryptionModuleResult> result);
 
   ~WebContentDecryptionModuleImpl() override;
 
   // blink::WebContentDecryptionModule implementation.
   blink::WebContentDecryptionModuleSession* createSession() override;
 
   void setServerCertificate(
       const uint8_t* server_certificate,
       size_t server_certificate_length,
       blink::WebContentDecryptionModuleResult result) override;
 
-  // Returns the CdmContext associated with this CDM, which must not be nullptr.
-  // TODO(jrummell): Figure out lifetimes, as WMPI may still use the decryptor
-  // after WebContentDecryptionModule is freed. http://crbug.com/330324
-  CdmContext* GetCdmContext();
+  // Returns a reference to the CDM used by |adapter_|.
+  scoped_refptr<MediaKeys> GetCdm();
 
  private:
   friend CdmSessionAdapter;
 
   // Takes reference to |adapter|.
   WebContentDecryptionModuleImpl(scoped_refptr<CdmSessionAdapter> adapter);
 
   scoped_refptr<CdmSessionAdapter> adapter_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentDecryptionModuleImpl);
 };
 
 // Allow typecasting from blink type as this is the only implementation.
 inline WebContentDecryptionModuleImpl* ToWebContentDecryptionModuleImpl(
     blink::WebContentDecryptionModule* cdm) {
   return static_cast<WebContentDecryptionModuleImpl*>(cdm);
 }
 
 }  // namespace media
 
 #endif  // MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULE_IMPL_H_