Remove dead code.

user_manager is never actually used, except to check if it's there.
UserManager::Get(), in turn, fails a CHECK if there is no UserManager.

Bug: none
Change-Id: I6e3adfc1b5143447f90e2f3cd04ff1e6af5d64b9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1846078
Auto-Submit: David Benjamin <davidben@chromium.org>
Reviewed-by: Mihai Sardarescu <msarda@chromium.org>
Commit-Queue: David Benjamin <davidben@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703754}

chrome/browser/profiles/profile_io_data.cc

@@ -267,19 +267,16 @@ void ProfileIOData::InitializeOnUIThread(Profile* profile) {
     params->system_key_slot_use_type = SystemKeySlotUseType::kUseForClientAuth;
   }
 
-  user_manager::UserManager* user_manager = user_manager::UserManager::Get();
-  if (user_manager) {
   const user_manager::User* user =
       chromeos::ProfileHelper::Get()->GetUserByProfile(profile);
   // No need to initialize NSS for users with empty username hash:
-    // Getters for a user's NSS slots always return NULL slot if the user's
+  // Getters for a user's NSS slots always return a null slot if the user's
   // username hash is empty, even when the NSS is not initialized for the
   // user.
   if (user && !user->username_hash().empty()) {
     params->username_hash = user->username_hash();
     DCHECK(!params->username_hash.empty());
-      base::PostTask(
-          FROM_HERE, {BrowserThread::IO},
+    base::PostTask(FROM_HERE, {BrowserThread::IO},
                    base::BindOnce(&StartNSSInitOnIOThread, user->GetAccountId(),
                                   user->username_hash(), profile->GetPath()));
 
@@ -290,7 +287,6 @@ void ProfileIOData::InitializeOnUIThread(Profile* profile) {
           SystemKeySlotUseType::kUseForClientAuthAndCertManagement;
     }
   }
-  }
 
   chromeos::CertificateProviderService* cert_provider_service =
       chromeos::CertificateProviderServiceFactory::GetForBrowserContext(