Keep only base/extractor.[cc|h].

base/security/rc4.h

-// Copyright 2005-2009 Google Inc.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//      http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-// ========================================================================
-
-#ifndef OMAHA_COMMON_SECURITY_RC4_H__
-#define OMAHA_COMMON_SECURITY_RC4_H__
-
-#include <inttypes.h>
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-typedef struct {
-  uint8_t S[256];
-  uint8_t i;
-  uint8_t j;
-} RC4_CTX;
-
-void RC4_setKey(RC4_CTX* ctx, const uint8_t* data, int len);
-void RC4_discard(RC4_CTX* ctx, int len);
-void RC4_crypt(RC4_CTX* ctx, const uint8_t* in, uint8_t* out, int len);
-void RC4_stream(RC4_CTX* ctx, uint8_t* out, int len);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif  // OMAHA_COMMON_SECURITY_RC4_H__