Code clean-up in AesDecryptor and test.

media/crypto/aes_decryptor.h

Index: media/crypto/aes_decryptor.h
diff --git a/media/crypto/aes_decryptor.h b/media/crypto/aes_decryptor.h
index 224035cfe76eefa316365c8e127c3f5b00031472..b9db003aab3726b8c15a579097d3fb0ce377ed99 100644
--- a/media/crypto/aes_decryptor.h
+++ b/media/crypto/aes_decryptor.h
@@ -86,6 +86,9 @@ class MEDIA_EXPORT AesDecryptor : public Decryptor {
     DISALLOW_COPY_AND_ASSIGN(DecryptionKey);
   };
 
+  void SetKey(const std::string& key_id, scoped_ptr<DecryptionKey> key);

[ddorwin, 2012/07/26 21:24:07]

Should note that this object takes ownership of key.

[xhwang, 2012/07/26 23:36:47]

Since scopted_ptr<> is move only, by passing in a scoped_ptr<DecryptionKey>, the
AesDecryptor has to take the ownership or the key is released. But I agree a
comment is clearer. Done.

+  DecryptionKey* GetKey(const std::string& key_id) const;

[ddorwin, 2012/07/26 21:24:07]

Who owns the key? If it's not a copy, should that be a const ref? Might then
need a "null" DecryptionKey.

[xhwang, 2012/07/26 23:36:47]

Added a comment that the AesDecryptor still owns the key.

+
   // KeyMap owns the DecryptionKey* and must delete them when they are
   // not needed any more.
   typedef base::hash_map<std::string, DecryptionKey*> KeyMap;
@@ -94,7 +97,7 @@ class MEDIA_EXPORT AesDecryptor : public Decryptor {
   // protect |key_map_|, the only member variable that is shared between
   // Decrypt() and other methods.
   KeyMap key_map_;  // Protected by the |key_map_lock_|.
-  base::Lock key_map_lock_;  // Protects the |key_map_|.
+  mutable base::Lock key_map_lock_;  // Protects the |key_map_|.
 
   // Make session ID unique per renderer by making it static.
   // TODO(xhwang): Make session ID more strictly defined if needed: