Add ManagedUserTokenFetcher to fetch scoped-down tokens.

chrome/browser/managed_mode/managed_user_token_fetcher.h

+// Copyright 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 CHROME_BROWSER_MANAGED_MODE_MANAGED_USER_TOKEN_FETCHER_H_
+#define CHROME_BROWSER_MANAGED_MODE_MANAGED_USER_TOKEN_FETCHER_H_
+
+#include <string>
+
+#include "base/callback_forward.h"
+#include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/string16.h"
+
+class GoogleServiceAuthError;
+class OAuth2TokenService;
+
+namespace net {
+class URLRequestContextGetter;
+}
+
+class ManagedUserTokenFetcher {

[Andrew T Wilson (Slow), 2013/05/27 13:52:15]

What does this class do? It's not clear to me what token is being returned? I
see that your implementation class is using GaiaOAuthClient, which is weird
since that's an OAuth1 class and OAuth2TokenService should already be giving you
an OAuth2 token to talk to whomever you wish.

[Bernhard Bauer, 2013/05/27 14:42:13]

Added a comment.
Is it? I'm using the GetTokensFromAuthCode() method, and in particular with the
oauth2_token_url, so it should send an OAuth2-compatible HTTP request to the
right endpoint, no?

+ public:
+  typedef base::Callback<void(const GoogleServiceAuthError& /* error */,
+                              const std::string& /* token */)> TokenCallback;
+
+  static scoped_ptr<ManagedUserTokenFetcher> Create(
+      OAuth2TokenService* oauth2_token_service,
+      net::URLRequestContextGetter* context);
+
+  virtual ~ManagedUserTokenFetcher();
+
+  virtual void Start(const std::string& managed_user_id,
+                     const string16& name,
+                     const std::string& device_name,
+                     const TokenCallback& callback) = 0;
+};
+
+#endif  // CHROME_BROWSER_MANAGED_MODE_MANAGED_USER_TOKEN_FETCHER_H_