[Cast] Cleanup: Remove TransportXXXXXSender, an unnecessary layer of indirection.

media/cast/transport/utility/transport_encryption_handler.h

Index: media/cast/transport/utility/transport_encryption_handler.h
diff --git a/media/cast/transport/utility/transport_encryption_handler.h b/media/cast/transport/utility/transport_encryption_handler.h
index dd740be2077dca7f50edfc03d7d068bcd04a6bce..06d0e3f34d61fc18efd9489d130510c0c46b8cc8 100644
--- a/media/cast/transport/utility/transport_encryption_handler.h
+++ b/media/cast/transport/utility/transport_encryption_handler.h
@@ -37,6 +37,9 @@ class TransportEncryptionHandler : public base::NonThreadSafe {
                const base::StringPiece& ciphertext,
                std::string* plaintext);
 
+  // TODO(miu): This naming is very misleading.  It should be called
+  // is_activated() since Initialize() without keys (i.e., cypto is disabled)
+  // may have succeeded.
   bool initialized() const { return initialized_; }
 
  private: