Add chromium side implementation of WebKit::WebCrypto.

content/renderer/webcrypto_impl.h

Index: content/renderer/webcrypto_impl.h
diff --git a/content/renderer/webcrypto_impl.h b/content/renderer/webcrypto_impl.h
new file mode 100644
index 0000000000000000000000000000000000000000..42081c4f185bd459ef4bd3c1e9a5e76875138f3f
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+++ b/content/renderer/webcrypto_impl.h
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+// Copyright (c) 2013 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_RENDERER_WEBCRYPTO_IMPL_H_
+#define CONTENT_RENDERER_WEBCRYPTO_IMPL_H_
+
+#include "base/compiler_specific.h"
+
+#include "third_party/WebKit/public/platform/WebCrypto.h"
+
+namespace content {
+
+class WebCryptoImpl : public WebKit::WebCrypto {
+ public:
+  virtual WebKit::WebCryptoOperation* digest(
+      const WebKit::WebCryptoAlgorithm& algorithm) OVERRIDE;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_WEBCRYPTO_IMPL_H_