Remove const from return value of FakeUserManager::Add*User family.

For consistency with FakeChromeUserManager, FakeUserManager::Add*User
family return non-const modified User*.

BUG=278643115
TEST=Tryjob

Change-Id: Iff840fcc565167e55a8aea10478a8e45bb0b074a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6054919
Commit-Queue: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1388970}
diff --git a/components/user_manager/fake_user_manager.cc b/components/user_manager/fake_user_manager.cc
index 34b7b7ee..897e906 100644
--- a/components/user_manager/fake_user_manager.cc
+++ b/components/user_manager/fake_user_manager.cc
@@ -37,25 +37,25 @@
   return account_id.GetUserEmail() + "-hash";
 }
 
-const User* FakeUserManager::AddUser(const AccountId& account_id) {
+User* FakeUserManager::AddUser(const AccountId& account_id) {
   return AddUserWithAffiliation(account_id, false);
 }
 
-const User* FakeUserManager::AddChildUser(const AccountId& account_id) {
+User* FakeUserManager::AddChildUser(const AccountId& account_id) {
   User* user = User::CreateRegularUser(account_id, UserType::kChild);
   user_storage_.emplace_back(user);
   users_.push_back(user);
   return user;
 }
 
-const User* FakeUserManager::AddGuestUser(const AccountId& account_id) {
+User* FakeUserManager::AddGuestUser(const AccountId& account_id) {
   User* user = User::CreateGuestUser(account_id);
   user_storage_.emplace_back(user);
   users_.push_back(user);
   return user;
 }
 
-const User* FakeUserManager::AddKioskAppUser(const AccountId& account_id) {
+User* FakeUserManager::AddKioskAppUser(const AccountId& account_id) {
   User* user = User::CreateKioskAppUser(account_id);
   user->set_username_hash(GetFakeUsernameHash(account_id));
   user_storage_.emplace_back(user);
@@ -63,8 +63,8 @@
   return user;
 }
 
-const User* FakeUserManager::AddUserWithAffiliation(const AccountId& account_id,
-                                                    bool is_affiliated) {
+User* FakeUserManager::AddUserWithAffiliation(const AccountId& account_id,
+                                              bool is_affiliated) {
   User* user = User::CreateRegularUser(account_id, UserType::kRegular);
   user->SetAffiliated(is_affiliated);
   user->set_username_hash(GetFakeUsernameHash(account_id));
@@ -73,8 +73,7 @@
   return user;
 }
 
-const user_manager::User* FakeUserManager::AddPublicAccountUser(
-    const AccountId& account_id) {
+User* FakeUserManager::AddPublicAccountUser(const AccountId& account_id) {
   User* user = User::CreatePublicAccountUserForTesting(account_id);
   user_storage_.emplace_back(user);
   users_.push_back(user);
diff --git a/components/user_manager/fake_user_manager.h b/components/user_manager/fake_user_manager.h
index f924ede..0a0d4ea 100644
--- a/components/user_manager/fake_user_manager.h
+++ b/components/user_manager/fake_user_manager.h
@@ -33,20 +33,18 @@
 
   // Create and add a new user. Created user is not affiliated with the domain,
   // that owns the device.
-  const User* AddUser(const AccountId& account_id);
-  const User* AddChildUser(const AccountId& account_id);
-  const User* AddGuestUser(const AccountId& account_id);
-  const User* AddKioskAppUser(const AccountId& account_id);
+  User* AddUser(const AccountId& account_id);
+  User* AddChildUser(const AccountId& account_id);
+  User* AddGuestUser(const AccountId& account_id);
+  User* AddKioskAppUser(const AccountId& account_id);
 
   // The same as AddUser() but allows to specify user affiliation with the
   // domain, that owns the device.
-  const User* AddUserWithAffiliation(const AccountId& account_id,
-                                     bool is_affiliated);
+  User* AddUserWithAffiliation(const AccountId& account_id, bool is_affiliated);
 
   // Create and add a new public account. Created user is not affiliated with
   // the domain, that owns the device.
-  virtual const user_manager::User* AddPublicAccountUser(
-      const AccountId& account_id);
+  user_manager::User* AddPublicAccountUser(const AccountId& account_id);
 
   void LogoutAllUsers();