arc: Implement safe access to ArcAuthService.

chrome/browser/chromeos/arc/arc_auth_service.cc

 // Copyright 2015 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/arc/arc_auth_service.h"
 
 #include <utility>
 
 #include "ash/shelf/shelf_delegate.h"
 #include "ash/shell.h"
@@ skipping 324 matching lines @@
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   return profile_ != nullptr;
 }
 
 void ArcAuthService::OnPrimaryUserProfilePrepared(Profile* profile) {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   DCHECK(profile && profile != profile_);
 
   Shutdown();
 
-  profile_ = profile;
-  SetState(State::STOPPED);
-
   if (!IsAllowedForProfile(profile))
     return;
 
   // TODO(khmel): Move this to IsAllowedForProfile.
   if (IsArcDisabledForEnterprise() && IsAccountManaged(profile)) {
     VLOG(2) << "Enterprise users are not supported in ARC.";
     return;
   }
 
+  profile_ = profile;
+  SetState(State::STOPPED);
+
   PrefServiceSyncableFromProfile(profile_)->AddSyncedPrefObserver(
       prefs::kArcEnabled, this);
 
   context_.reset(new ArcAuthContext(this, profile_));
 
   // In case UI is disabled we assume that ARC is opted-in.
   if (IsOptInVerificationDisabled()) {
     auth_code_.clear();
     StartArc();
     return;
@@ skipping 263 matching lines @@
 }
 
 bool ArcAuthService::IsArcManaged() const {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   DCHECK(profile_);
   return profile_->GetPrefs()->IsManagedPreference(prefs::kArcEnabled);
 }
 
 bool ArcAuthService::IsArcEnabled() const {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
+  if (!IsAllowed())
+    return false;
+
   DCHECK(profile_);
   return profile_->GetPrefs()->GetBoolean(prefs::kArcEnabled);
 }
 
 void ArcAuthService::EnableArc() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   DCHECK(profile_);
 
   if (IsArcEnabled()) {
     OnOptInPreferenceChanged();
@@ skipping 101 matching lines @@
       return os << kStateFetchingCode;
     case ArcAuthService::State::ACTIVE:
       return os << kStateActive;
     default:
       NOTREACHED();
       return os;
   }
 }
 
 }  // namespace arc