Add the Mojo implementation of authenticator.mojom's MakeCredential.

content/browser/webauth/authenticator_impl.h

+// Copyright 2017 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_BROWSER_WEBAUTH_AUTHENTICATOR_IMPL_H_
+#define CONTENT_BROWSER_WEBAUTH_AUTHENTICATOR_IMPL_H_
+
+#include <vector>
+
+#include "base/cancelable_callback.h"
+#include "base/macros.h"
+#include "mojo/public/cpp/bindings/binding.h"
+#include "mojo/public/cpp/bindings/interface_request.h"
+#include "third_party/WebKit/public/platform/modules/webauth/authenticator.mojom.h"
+#include "url/origin.h"
+
+namespace service_manager {
+struct BindSourceInfo;
+}
+
+namespace content {
+
+class RenderFrameHost;
+
+// Implementation of the public Authenticator interface.
+class AuthenticatorImpl : public webauth::mojom::Authenticator {

[jochen (gone - plz use gerrit), 2017/06/30 08:15:10]

this should be class CONTENT_EXPORT AuthenticatorImpl : public
NON_EXPORTED_BASED(webauth::mojom::Authenticator) {

You'll also need to #include content/common/content_export.h

+ public:
+  static void Create(RenderFrameHost* render_frame_host,
+                     const service_manager::BindSourceInfo& source_info,
+                     webauth::mojom::AuthenticatorRequest request);
+  ~AuthenticatorImpl() override;
+
+  void set_connection_error_handler(const base::Closure& error_handler) {
+    connection_error_handler_ = error_handler;
+  }
+
+ private:
+  explicit AuthenticatorImpl(RenderFrameHost* render_frame_host);
+
+  // mojom:Authenticator
+  void MakeCredential(
+      webauth::mojom::RelyingPartyAccountPtr account,
+      std::vector<webauth::mojom::ScopedCredentialParametersPtr> parameters,
+      const std::vector<uint8_t>& challenge,
+      webauth::mojom::ScopedCredentialOptionsPtr options,
+      MakeCredentialCallback callback) override;
+
+  base::Closure connection_error_handler_;
+  base::CancelableClosure timeout_callback_;
+  url::Origin caller_origin_;
+  DISALLOW_COPY_AND_ASSIGN(AuthenticatorImpl);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_WEBAUTH_AUTHENTICATOR_IMPL_H_