Refactor AO2TS to make it easier to componentize.

components/signin/core/browser/profile_oauth2_token_service.cc

 // Copyright 2014 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.
 
 #include "components/signin/core/browser/profile_oauth2_token_service.h"
 
-#include "base/bind.h"
-#include "base/message_loop/message_loop.h"
-#include "base/stl_util.h"
-#include "base/time/time.h"
-#include "components/signin/core/browser/signin_client.h"
-#include "components/signin/core/browser/signin_error_controller.h"
-#include "google_apis/gaia/gaia_auth_util.h"
-#include "net/url_request/url_request_context_getter.h"
+void ProfileOAuth2TokenService::OnRefreshTokenAvailable(
+    const std::string& account_id) {
+  CancelRequestsForAccount(account_id);
+  ClearCacheForAccount(account_id);
+}
 
-ProfileOAuth2TokenService::ProfileOAuth2TokenService()
-    : client_(NULL),
-      signin_error_controller_(NULL) {}
+ProfileOAuth2TokenService::ProfileOAuth2TokenService(
+    OAuth2TokenServiceDelegate* delegate)
+    : OAuth2TokenService(delegate) {
+  AddObserver(this);
+}
 
-ProfileOAuth2TokenService::~ProfileOAuth2TokenService() {}
-
-void ProfileOAuth2TokenService::Initialize(
-    SigninClient* client,
-    SigninErrorController* signin_error_controller) {
-  DCHECK(client);
-  DCHECK(!client_);
-  DCHECK(signin_error_controller);
-  DCHECK(!signin_error_controller_);
-  client_ = client;
-  signin_error_controller_ = signin_error_controller;
+ProfileOAuth2TokenService::~ProfileOAuth2TokenService() {
+  RemoveObserver(this);
 }
 
 void ProfileOAuth2TokenService::Shutdown() {
-  DCHECK(client_) << "Shutdown() called without matching call to Initialize()";
-}
-
-net::URLRequestContextGetter* ProfileOAuth2TokenService::GetRequestContext() {
-  return NULL;
-}
-
-void ProfileOAuth2TokenService::UpdateAuthError(
-    const std::string& account_id,
-    const GoogleServiceAuthError& error) {
-  NOTREACHED();
-}
-
-void ProfileOAuth2TokenService::ValidateAccountId(
-    const std::string& account_id) const {
-  DCHECK(!account_id.empty());
-
-  // If the account is given as an email, make sure its a canonical email.
-  // Note that some tests don't use email strings as account id, and after
-  // the gaia id migration it won't be an email.  So only check for
-  // canonicalization if the account_id is suspected to be an email.
-  if (account_id.find('@') != std::string::npos)
-    DCHECK_EQ(gaia::CanonicalizeEmail(account_id), account_id);
-}
-
-std::vector<std::string> ProfileOAuth2TokenService::GetAccounts() {
-  NOTREACHED();
-  return std::vector<std::string>();
+  CancelAllRequests();
+  GetDelegate()->Shutdown();
 }
 
 void ProfileOAuth2TokenService::LoadCredentials(
     const std::string& primary_account_id) {
-  // Empty implementation by default.
+  GetDelegate()->LoadCredentials(primary_account_id);
 }
 
 void ProfileOAuth2TokenService::UpdateCredentials(
     const std::string& account_id,
     const std::string& refresh_token) {
-  NOTREACHED();
+  GetDelegate()->UpdateCredentials(account_id, refresh_token);
 }
 
-void ProfileOAuth2TokenService::RevokeAllCredentials() {
-  // Empty implementation by default.
-}
+void ProfileOAuth2TokenService::RevokeCredentials(
+    const std::string& account_id) {
+  CancelRequestsForAccount(account_id);
+  ClearCacheForAccount(account_id);

[gogerald1, 2015/06/25 14:06:18]

try to save one function lookup and call, but since we already register this
class as an observer, so it will not going to save anything, move them to
observer callback function.

+  GetDelegate()->RevokeCredentials(account_id);
+}