Revert of Clean up Smart Lock cryptohome keys logic:

chrome/browser/chromeos/login/session/user_session_manager.cc

Index: chrome/browser/chromeos/login/session/user_session_manager.cc
diff --git a/chrome/browser/chromeos/login/session/user_session_manager.cc b/chrome/browser/chromeos/login/session/user_session_manager.cc
index c9abbfbf612be6813adf288985b58422bb127ee0..98ac1177d6157950e5794d314f02924a06a7d6b7 100644
--- a/chrome/browser/chromeos/login/session/user_session_manager.cc
+++ b/chrome/browser/chromeos/login/session/user_session_manager.cc
@@ -1299,7 +1299,7 @@
 
 void UserSessionManager::UpdateEasyUnlockKeys(const UserContext& user_context) {
   // Skip key update because FakeCryptohomeClient always return success
-  // and RefreshKeys op expects a failure to stop. As a result, some tests would
+  // and RemoveKey op expects a failure to stop. As a result, some tests would
   // timeout.
   // TODO(xiyuan): Revisit this when adding tests.
   if (!base::SysInfo::IsRunningOnChromeOS())
@@ -1325,16 +1325,23 @@
         EasyUnlockScreenlockStateHandler::NO_HARDLOCK);
   }
 
-  base::ListValue empty_list;
-  if (!device_list)
-    device_list = &empty_list;
-
   EasyUnlockKeyManager* key_manager = GetEasyUnlockKeyManager();
   running_easy_unlock_key_ops_ = true;
-  key_manager->RefreshKeys(
-      user_context, *device_list,
-      base::Bind(&UserSessionManager::OnEasyUnlockKeyOpsFinished, AsWeakPtr(),
-                 user_context.GetUserID()));
+  if (device_list) {
+    key_manager->RefreshKeys(
+        user_context,
+        *device_list,
+        base::Bind(&UserSessionManager::OnEasyUnlockKeyOpsFinished,
+                   AsWeakPtr(),
+                   user_context.GetUserID()));
+  } else {
+    key_manager->RemoveKeys(
+        user_context,
+        0,
+        base::Bind(&UserSessionManager::OnEasyUnlockKeyOpsFinished,
+                   AsWeakPtr(),
+                   user_context.GetUserID()));
+  }
 }
 
 void UserSessionManager::AttemptRestart(Profile* profile) {