Refactor AO2TS to make it easier to componentize.

google_apis/gaia/fake_oauth2_token_service_delegate.h

+#ifndef GOOGLE_APIS_GAIA_FAKE_OAUTH2_TOKEN_SERVICE_DELEGATE_H_
+#define GOOGLE_APIS_GAIA_FAKE_OAUTH2_TOKEN_SERVICE_DELEGATE_H_
+
+#include <set>
+#include <string>
+
+#include "google_apis/gaia/oauth2_token_service_delegate.h"
+
+namespace net {
+class URLRequestContextGetter;
+}
+
+class FakeOAuth2TokenServiceDelegate : public OAuth2TokenServiceDelegate {
+ public:
+  FakeOAuth2TokenServiceDelegate();
+  ~FakeOAuth2TokenServiceDelegate() override;
+
+  // OAuth2TokenService overrides.
+  net::URLRequestContextGetter* GetRequestContext() const override;
+
+  OAuth2AccessTokenFetcher* CreateAccessTokenFetcher(
+      const std::string& account_id,
+      net::URLRequestContextGetter* getter,
+      OAuth2AccessTokenConsumer* consumer) override;
+
+  bool RefreshTokenIsAvailable(const std::string& account_id) const override;
+  std::string GetRefreshToken(const std::string& account_id) const override;
+  void UpdateAuthError(const std::string& account_id,
+                       const GoogleServiceAuthError& error) override;
+
+  std::vector<std::string> GetAccounts() override;
+  void RevokeAllCredentials() override;
+
+  void AddAccount(const std::string& account_id);
+  void RemoveAccount(const std::string& account_id);
+
+  void set_request_context(net::URLRequestContextGetter* request_context) {
+    request_context_ = request_context;
+  }
+
+ private:
+  std::set<std::string> account_ids_;
+
+  net::URLRequestContextGetter* request_context_;  // weak
+
+  DISALLOW_COPY_AND_ASSIGN(FakeOAuth2TokenServiceDelegate);
+};
+
+#endif