Migrate --enable-arc and --arc-available part 1.

chrome/browser/chromeos/login/session/chrome_session_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/chromeos/login/session/chrome_session_manager.h"
 
 #include <memory>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 15 matching lines @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/signin/signin_manager_factory.h"
 #include "chrome/browser/ui/ash/ash_util.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/pref_names.h"
 #include "chromeos/audio/cras_audio_handler.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/cryptohome/cryptohome_parameters.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/session_manager_client.h"
-#include "components/arc/arc_bridge_service.h"
 #include "components/prefs/pref_service.h"
 #include "components/signin/core/account_id/account_id.h"
 #include "components/signin/core/browser/signin_manager.h"
 #include "components/user_manager/user_manager.h"
 #include "components/user_manager/user_names.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/common/content_switches.h"
 
 namespace chromeos {
 
@@ skipping 52 matching lines @@
       // This is possible if crash occured after profile removal
       // (see crbug.com/178290 for some more info).
       LOG(ERROR) << "Could not get active user after crash.";
       return;
     }
     user_session_mgr->InitRlz(user_profile);
     user_session_mgr->InitializeCerts(user_profile);
     user_session_mgr->InitializeCRLSetFetcher(user);
     user_session_mgr->InitializeCertificateTransparencyComponents(user);
 
-    if (arc::ArcBridgeService::GetEnabled(
-            base::CommandLine::ForCurrentProcess())) {
-      arc::ArcServiceLauncher::Get()->OnPrimaryUserProfilePrepared(
-          user_profile);
-    }
+    arc::ArcServiceLauncher::Get()->OnPrimaryUserProfilePrepared(user_profile);

[hidehiko, 2017/01/24 10:57:36]

Note: because ArcServiceLauncher instance is always created regardless of
IsArcAvailable(), we should be able to call this unconditionally.

Note that, in case of that IsArcAvailable() returns false,
ArcSessionManager::OnPrimaryUserProfilePrepared() handles it.

[Luis Héctor Chávez, 2017/01/24 17:00:37]

Please note this in a comment.

Also, I believe the motivation behind the check was to avoid
instantiating/initializing stuff unless it was necessary, so I'd vote to keep it
unless it's causing some complication elsewhere.

[hidehiko, 2017/01/24 18:05:56]

I prefer the consistency, here.
ArcService instances are initialized regardless of the IsArcAvailable(), so I
think it makes sense to call OnPrimaryUserProfilePreapred() as well, where some
services are initialized in the function.

So, the diff in a case IsArcAvailable() returns false then is whether Shutdown()
is called or not, in ArcSessionManager. However, if IsArcAvailable() returns
false, no-one can starts arc so it should be almost no-op. Thus, I do not think
we have much benefit by culling the call.

WDYT?

[Luis Héctor Chávez, 2017/01/26 17:48:26]

I still believe we should try to avoid even instantiating the services when ARC
is not available, but I also buy the consistency argument. Let's fix that in a
separate change.

[hidehiko, 2017/01/30 13:15:18]

Thanks. I created a tracking bug. crbug.com/686703.

 
     // Send the PROFILE_PREPARED notification and call SessionStarted()
     // so that the Launcher and other Profile dependent classes are created.
     content::NotificationService::current()->Notify(
         chrome::NOTIFICATION_LOGIN_USER_PROFILE_PREPARED,
         content::NotificationService::AllSources(),
         content::Details<Profile>(user_profile));
 
     // This call will set session state to SESSION_STATE_ACTIVE (same one).
     session_manager::SessionManager::Get()->SessionStarted();
@@ skipping 111 matching lines @@
                                               const std::string& user_id_hash,
                                               bool browser_restart) {
   BootTimesRecorder* btl = BootTimesRecorder::Get();
   btl->AddLoginTimeMarker("UserLoggedIn-Start", false);
   session_manager::SessionManager::NotifyUserLoggedIn(
       user_account_id, user_id_hash, browser_restart);
   btl->AddLoginTimeMarker("UserLoggedIn-End", false);
 }
 
 }  // namespace chromeos