After locking a profile and showing the User Manager, make Guest the active profile

chrome/browser/profiles/profiles_state.cc

 // Copyright 2013 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/profiles/profiles_state.h"
 
 #include "base/files/file_path.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 39 matching lines @@
   registry->RegisterBooleanPref(prefs::kBrowserGuestModeEnabled, true);
   registry->RegisterBooleanPref(prefs::kBrowserAddPersonEnabled, true);
 }
 
 base::string16 GetAvatarNameForProfile(const base::FilePath& profile_path) {
   base::string16 display_name;
 
   if (profile_path == ProfileManager::GetGuestProfilePath()) {
     display_name = l10n_util::GetStringUTF16(IDS_GUEST_PROFILE_NAME);
   } else {
-    ProfileInfoCache& cache =
+    const ProfileInfoCache& cache =
         g_browser_process->profile_manager()->GetProfileInfoCache();
     size_t index = cache.GetIndexOfProfileWithPath(profile_path);
 
     if (index == std::string::npos)
       return l10n_util::GetStringUTF16(IDS_SINGLE_PROFILE_DISPLAY_NAME);
 
     // Using the --new-avatar-menu flag, there's a couple of rules about what
     // the avatar button displays. If there's a single profile, with a default
     // name (i.e. of the form Person %d) not manually set, it should display
     // IDS_SINGLE_PROFILE_DISPLAY_NAME. If the profile is signed in but is using
@@ skipping 20 matching lines @@
                              gfx::CHARACTER_BREAK);
   if (profile->IsSupervised()) {
     name = l10n_util::GetStringFUTF16(IDS_SUPERVISED_USER_NEW_AVATAR_LABEL,
                                       name);
   }
   return name;
 }
 
 void UpdateProfileName(Profile* profile,
                        const base::string16& new_profile_name) {
-  ProfileInfoCache& cache =
+  const ProfileInfoCache& cache =
       g_browser_process->profile_manager()->GetProfileInfoCache();
   size_t profile_index = cache.GetIndexOfProfileWithPath(profile->GetPath());
   if (profile_index == std::string::npos)
     return;
 
   if (new_profile_name == cache.GetNameOfProfileAtIndex(profile_index))
     return;
 
   // This is only called when updating the profile name through the UI,
   // so we can assume the user has done this on purpose.
@@ skipping 37 matching lines @@
   DCHECK(profile);
   GAIAInfoUpdateServiceFactory::GetInstance()->GetForProfile(profile)->Update();
 }
 
 SigninErrorController* GetSigninErrorController(Profile* profile) {
   ProfileOAuth2TokenService* token_service =
       ProfileOAuth2TokenServiceFactory::GetForProfile(profile);
   return token_service ? token_service->signin_error_controller() : NULL;
 }
 
+Profile* SetActiveProfileToGuestIfLocked() {
+  Profile* active_profile = ProfileManager::GetLastUsedProfile();
+  DCHECK(active_profile);
+
+  ProfileManager* profile_manager = g_browser_process->profile_manager();
+  const ProfileInfoCache& cache = profile_manager->GetProfileInfoCache();
+  size_t index = cache.GetIndexOfProfileWithPath(active_profile->GetPath());
+  if (!cache.ProfileIsSigninRequiredAtIndex(index))
+    return NULL;
+
+  // The guest profile must have been loaded already.
+  Profile* guest_profile = profile_manager->GetProfile(
+      ProfileManager::GetGuestProfilePath());
+  CHECK(guest_profile);

[Alexei Svitkine (slow), 2014/09/22 16:58:00]

Nit: DCHECK().

If it's NULL, it will crash on line 177 anyway, so no need for CHECK here.

[noms (inactive), 2014/09/22 21:41:49]

Done.

+
+  PrefService* local_state = g_browser_process->local_state();
+  DCHECK(local_state);
+  local_state->SetString(prefs::kProfileLastUsed,
+                         guest_profile->GetPath().BaseName().MaybeAsASCII());
+  return guest_profile;
+}
+
 }  // namespace profiles