Track when and how a profile is signed out via UMA.

chrome/browser/services/gcm/fake_signin_manager.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 "chrome/browser/services/gcm/fake_signin_manager.h"
 
 #include "base/observer_list.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/chrome_signin_client_factory.h"
@@ skipping 23 matching lines @@
 FakeSigninManager::~FakeSigninManager() {
 }
 
 void FakeSigninManager::SignIn(const std::string& username) {
   SetAuthenticatedUsername(username);
   FOR_EACH_OBSERVER(Observer,
                     observer_list_,
                     GoogleSigninSucceeded(username, std::string()));
 }
 
-void FakeSigninManager::SignOut() {
+void FakeSigninManager::SignOut(
+    signin_metrics::ProfileSignout signout_source_metric) {
   const std::string username = GetAuthenticatedUsername();
   clear_authenticated_username();
   profile_->GetPrefs()->ClearPref(prefs::kGoogleServicesUsername);
   FOR_EACH_OBSERVER(Observer, observer_list_, GoogleSignedOut(username));
 }
 
 // static
 KeyedService* FakeSigninManager::Build(content::BrowserContext* context) {
   return new FakeSigninManager(Profile::FromBrowserContext(context));
 }
 
 }  // namespace gcm