Hide screen lock options button in confirm lock

Hide the screen lock options button in the confirmation stage of
SetupChooseLockPassword, so the user cannot skip out of that screen
while the screen lock is being saved.

Test: Manual
Bug: 63526104
Change-Id: I8ee8938f3ddcd9f0ff3b1812fcae667eddaf09ab

src/com/android/settings/password/ChooseLockPassword.java

@@ -202,7 +202,7 @@ public class ChooseLockPassword extends SettingsActivity {
         private SaveAndFinishWorker mSaveAndFinishWorker;
         private int mRequestedQuality = DevicePolicyManager.PASSWORD_QUALITY_NUMERIC;
         private ChooseLockSettingsHelper mChooseLockSettingsHelper;
-        private Stage mUiStage = Stage.Introduction;
+        protected Stage mUiStage = Stage.Introduction;
         private PasswordRequirementAdapter mPasswordRequirementAdapter;
         private GlifLayout mLayout;
         protected boolean mForFingerprint;
@@ -820,7 +820,7 @@ public class ChooseLockPassword extends SettingsActivity {
         /**
          * Update the hint based on current Stage and length of password entry
          */
-        private void updateUi() {
+        protected void updateUi() {
             final boolean canInput = mSaveAndFinishWorker == null;
             String password = mPasswordEntry.getText().toString();
             final int length = password.length();