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

chrome/browser/extensions/extension_gcm_app_handler_unittest.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/extensions/extension_gcm_app_handler.h"
 
 #include <vector>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 324 matching lines @@
   void UninstallExtension(const Extension* extension) {
     extension_service_->UninstallExtension(extension->id(), false, NULL);
   }
 
   void SignIn(const std::string& username) {
     signin_manager_->SignIn(username);
     waiter_.PumpIOLoop();
   }
 
   void SignOut() {
-    signin_manager_->SignOut();
+    signin_manager_->SignOut(signin_metrics::SIGNOUT_TEST);
     waiter_.PumpIOLoop();
   }
 
   void Register(const std::string& app_id,
                 const std::vector<std::string>& sender_ids) {
     GetGCMDriver()->Register(
         app_id,
         sender_ids,
         base::Bind(&ExtensionGCMAppHandlerTest::RegisterCompleted,
                    base::Unretained(this)));
@@ skipping 127 matching lines @@
 
   // App handler is removed when the extension is updated to the version that
   // has GCM permission removed.
   UpdateExtension(extension, "good2.crx");
   waiter()->PumpUILoop();
   EXPECT_TRUE(gcm_app_handler()->app_handler_count_drop_to_zero());
   EXPECT_FALSE(HasAppHandlers(extension->id()));
 }
 
 }  // namespace extensions