Revert 147169 - Add support for encrypted WebM files as defined in the RFC.

media/webm/webm_content_encodings.h

Index: media/webm/webm_content_encodings.h
===================================================================
--- media/webm/webm_content_encodings.h	(revision 147171)
+++ media/webm/webm_content_encodings.h	(working copy)
@@ -42,11 +42,6 @@
     kEncAlgoAes = 5,
   };
 
-  enum CipherMode {
-    kCipherModeInvalid = 0,
-    kCipherModeCtr = 1,
-  };
-
   ContentEncoding();
   ~ContentEncoding();
 
@@ -69,9 +64,6 @@
 
   void SetEncryptionKeyId(const uint8* encryption_key_id, int size);
 
-  CipherMode cipher_mode() const { return cipher_mode_; }
-  void set_cipher_mode(CipherMode mode) { cipher_mode_ = mode; }
-
  private:
   int64 order_;
   Scope scope_;
@@ -79,7 +71,6 @@
   EncryptionAlgo encryption_algo_;
   scoped_array<uint8> encryption_key_id_;
   int encryption_key_id_size_;
-  CipherMode cipher_mode_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentEncoding);
 };