Handle createCDM() when frame destroyed

media/blink/webencryptedmediaclient_impl.h

Index: media/blink/webencryptedmediaclient_impl.h
diff --git a/media/blink/webencryptedmediaclient_impl.h b/media/blink/webencryptedmediaclient_impl.h
index d101ecb9549caace1e1b9d4cd28c40519e8c7251..7b606dc448477a473de426c833fbce434c04eb27 100644
--- a/media/blink/webencryptedmediaclient_impl.h
+++ b/media/blink/webencryptedmediaclient_impl.h
@@ -9,8 +9,10 @@
 
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
 #include "media/base/cdm_factory.h"
 #include "media/base/media_export.h"
+#include "third_party/WebKit/public/platform/WebContentDecryptionModuleResult.h"
 #include "third_party/WebKit/public/platform/WebEncryptedMediaClient.h"
 #include "third_party/WebKit/public/web/WebSecurityOrigin.h"
 
@@ -29,6 +31,12 @@ class MEDIA_EXPORT WebEncryptedMediaClientImpl
   virtual void requestMediaKeySystemAccess(
       blink::WebEncryptedMediaRequest request);
 
+  // Create the CDM for |key_system| and |security_origin|. The caller owns
+  // the created cdm (passed back using |result|).
+  void CreateCdm(const blink::WebString& key_system,
+                 const blink::WebSecurityOrigin& security_origin,
+                 blink::WebContentDecryptionModuleResult result);
+
  private:
   // Report usage of key system to UMA. There are 2 different counts logged:
   // 1. The key system is requested.
@@ -45,6 +53,8 @@ class MEDIA_EXPORT WebEncryptedMediaClientImpl
   Reporters reporters_;
 
   scoped_ptr<CdmFactory> cdm_factory_;
+
+  base::WeakPtrFactory<WebEncryptedMediaClientImpl> weak_factory_;
 };
 
 }  // namespace media