Refactor AO2TS to make it easier to componentize.

extensions/shell/browser/shell_oauth2_token_service_delegate.h

+// Copyright 2015 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 EXTENSIONS_SHELL_BROWSER_SHELL_OAUTH2_TOKEN_SERVICE_DELEGATE_H_
+#define EXTENSIONS_SHELL_BROWSER_SHELL_OAUTH2_TOKEN_SERVICE_DELEGATE_H_
+
+#include <string>
+
+#include "content/public/browser/browser_context.h"
+#include "google_apis/gaia/oauth2_access_token_fetcher_impl.h"
+#include "google_apis/gaia/oauth2_token_service_delegate.h"
+
+namespace content {
+class BrowserContext;
+}
+
+namespace extensions {
+
+class ShellOAuth2TokenServiceDelegate : public OAuth2TokenServiceDelegate {
+ public:
+  ShellOAuth2TokenServiceDelegate(content::BrowserContext* browser_context,
+                                  std::string account_id,
+                                  std::string refresh_token);
+  ~ShellOAuth2TokenServiceDelegate() override;
+
+  bool RefreshTokenIsAvailable(const std::string& account_id) const override;
+
+  OAuth2AccessTokenFetcher* CreateAccessTokenFetcher(
+      const std::string& account_id,
+      net::URLRequestContextGetter* getter,
+      OAuth2AccessTokenConsumer* consumer) override;
+  net::URLRequestContextGetter* GetRequestContext() const override;
+
+  std::vector<std::string> GetAccounts() override;
+
+  void UpdateCredentials(const std::string& account_id,
+                         const std::string& refresh_token) override;
+
+ private:
+  // Not owned.
+  content::BrowserContext* browser_context_;
+
+  // User account id, such as "foo@gmail.com".
+  std::string account_id_;
+
+  // Cached copy of an OAuth2 refresh token. Not stored on disk.
+  std::string refresh_token_;
+
+  DISALLOW_COPY_AND_ASSIGN(ShellOAuth2TokenServiceDelegate);
+};
+
+}  // namespace extensions
+#endif