Record shutdown type UMA

chrome/browser/browser_shutdown.h

 // 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.
 
 #ifndef CHROME_BROWSER_BROWSER_SHUTDOWN_H_
 #define CHROME_BROWSER_BROWSER_SHUTDOWN_H_
 
 #include "build/build_config.h"
 
 class PrefRegistrySimple;
@@ skipping 18 matching lines @@
   // an uninitialized value
   NOT_VALID = 0,
   // the last browser window was closed
   WINDOW_CLOSE,
   // user clicked on the Exit menu item
   BROWSER_EXIT,
   // windows is logging off or shutting down
   END_SESSION
 };
 
+constexpr int kNumShutdownTypes = END_SESSION + 1;
+
 void RegisterPrefs(PrefRegistrySimple* registry);
 
 // Called when the browser starts shutting down so that we can measure shutdown
 // time.
 void OnShutdownStarting(ShutdownType type);
 
 // Get the current shutdown type.
 ShutdownType GetShutdownType();
 
 #if !defined(OS_ANDROID)
 // Performs the shutdown tasks that need to be done before
 // BrowserProcess and the various threads go away.
 //
 // Returns true if the session should be restarted.
 bool ShutdownPreThreadsStop();
 
+// Records the shutdown related prefs, and returns true when we should restart

[sky, 2016/09/13 13:21:14]

How about: Returns true if the browser should be restarted on exit.

[hashimoto, 2016/09/13 22:18:22]

Done.

+// the last session.
+bool RecordShutdownInfoPrefs();
+
 // Performs the remaining shutdown tasks after all threads but the
 // main thread have been stopped.  This includes deleting g_browser_process.
 //
 // See |browser_shutdown::Flags| for the possible flag values and their effects.
 void ShutdownPostThreadsStop(int shutdown_flags);
 #endif
 
 // Called at startup to create a histogram from our previous shutdown time.
 void ReadLastShutdownInfo();
 
@@ skipping 19 matching lines @@
 bool IsTryingToQuit();
 
 // Starts to collect shutdown traces. On ChromeOS this will start immediately
 // on AttemptUserExit() and all other systems will start once all tabs are
 // closed.
 void StartShutdownTracing();
 
 }  // namespace browser_shutdown
 
 #endif  // CHROME_BROWSER_BROWSER_SHUTDOWN_H_