Now CHECKs to make sure we log out before clearing the token db

chrome/browser/signin/token_service.cc

 // Copyright (c) 2012 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 "chrome/browser/signin/token_service.h"
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/string_util.h"
+#include "chrome/browser/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/net/gaia/gaia_auth_fetcher.h"
 #include "chrome/common/net/gaia/gaia_constants.h"
+#include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_source.h"
 #include "net/url_request/url_request_context_getter.h"
 
 using content::BrowserThread;
 
 namespace {
 
 // List of services that are capable of ClientLogin-based authentication.
@@ skipping 101 matching lines @@
 
 void TokenService::SaveAuthTokenToDB(const std::string& service,
                                      const std::string& auth_token) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (web_data_service_.get())
     web_data_service_->SetTokenForService(service, auth_token);
 }
 
 void TokenService::EraseTokensFromDB() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  // Try to track down http://crbug.com/121755 - we should never clear the
+  // token DB while we're still logged in.
+  if (profile_) {
+    std::string user = profile_->GetPrefs()->GetString(
+        prefs::kGoogleServicesUsername);

[tim (not reviewing), 2012/04/25 18:37:59]

Is there anything else in TokenService that expects / requires SigninManager to
be initialized before it? Not a big deal or a problem in practice (or tests?),
maybe augment the comment just in case. 

+    CHECK(user.empty());
+  }
   if (web_data_service_.get())
     web_data_service_->RemoveAllTokens();
 }
 
 bool TokenService::TokensLoadedFromDB() const {
   return tokens_loaded_;
 }
 
 // static
 int TokenService::GetServiceIndex(const std::string& service) {
@@ skipping 215 matching lines @@
 }
 
 void TokenService::Observe(int type,
                            const content::NotificationSource& source,
                            const content::NotificationDetails& details) {
   DCHECK_EQ(type, chrome::NOTIFICATION_TOKEN_UPDATED);
   TokenAvailableDetails* tok_details =
       content::Details<TokenAvailableDetails>(details).ptr();
   OnIssueAuthTokenSuccess(tok_details->service(), tok_details->token());
 }