html_viewer: Move webcrypto to a place where html_viewer can use it.

content/child/webcrypto/crypto_data.h

-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CONTENT_CHILD_WEBCRYPTO_CRYPTO_DATA_H_
-#define CONTENT_CHILD_WEBCRYPTO_CRYPTO_DATA_H_
-
-#include <string>
-#include <vector>
-
-#include "base/basictypes.h"
-#include "content/common/content_export.h"
-#include "third_party/WebKit/public/platform/WebVector.h"
-
-namespace content {
-
-namespace webcrypto {
-
-// Helper to pass around a range of immutable bytes. This is conceptually
-// similar to base::StringPiece, but for crypto byte data.
-//
-// The data used at construction is NOT owned, and should remain valid as long
-// as the CryptoData is being used.
-class CONTENT_EXPORT CryptoData {
- public:
-  // Constructs empty data.
-  CryptoData();
-
-  CryptoData(const unsigned char* bytes, unsigned int byte_length);
-
-  // These constructors do NOT copy the data. Hence the base pointer should
-  // remain valid for the lifetime of CryptoData.
-  explicit CryptoData(const std::vector<unsigned char>& bytes);
-  explicit CryptoData(const std::string& bytes);
-  explicit CryptoData(const blink::WebVector<unsigned char>& bytes);
-
-  const unsigned char* bytes() const { return bytes_; }
-  unsigned int byte_length() const { return byte_length_; }
-
- private:
-  const unsigned char* const bytes_;
-  const unsigned int byte_length_;
-};
-
-}  // namespace webcrypto
-
-}  // namespace content
-
-#endif  // CONTENT_CHILD_WEBCRYPTO_CRYPTO_DATA_H_