1/n Start adding Face settings (base, intro)

This change refactors common biometric settings code as well to minimize
duplicated code in areas such as:
    Preference Controller
    EnrollBase
    EnrollIntro

This change also updates ChooseLock to have Face + Pin/Pattern/Pass

Bug: 110589286

Test: Fingerprint settings/enrollment still works
Test: make -j56 RunSettingsRoboTests
Change-Id: Ie35406a01b85617423beece42683ac086e9bc4a7

src/com/android/settings/biometrics/face/FaceEnrollIntroduction.java

@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+
+package com.android.settings.biometrics.face;
+
+import android.app.admin.DevicePolicyManager;
+import android.content.Intent;
+import android.hardware.face.FaceManager;
+import android.os.Bundle;
+import android.widget.Button;
+import android.widget.TextView;
+
+import com.android.internal.logging.nano.MetricsProto;
+import com.android.settings.R;
+import com.android.settings.Utils;
+import com.android.settings.biometrics.BiometricEnrollIntroduction;
+import com.android.settings.password.ChooseLockSettingsHelper;
+import com.android.settingslib.RestrictedLockUtils;
+import com.android.setupwizardlib.span.LinkSpan;
+
+public class FaceEnrollIntroduction extends BiometricEnrollIntroduction {
+
+    private static final String TAG = "FaceIntro";
+
+    private FaceManager mFaceManager;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        mFaceManager = Utils.getFaceManagerOrNull(this);
+    }
+
+    @Override
+    protected boolean isDisabledByAdmin() {
+        return RestrictedLockUtils.checkIfKeyguardFeaturesDisabled(
+                this, DevicePolicyManager.KEYGUARD_DISABLE_FACE, mUserId) != null;
+    }
+
+    @Override
+    protected int getLayoutResource() {
+        return R.layout.face_enroll_introduction;
+    }
+
+    @Override
+    protected int getHeaderResDisabledByAdmin() {
+        return R.string.security_settings_face_enroll_introduction_title_unlock_disabled;
+    }
+
+    @Override
+    protected int getHeaderResDefault() {
+        return R.string.security_settings_face_enroll_introduction_title;
+    }
+
+    @Override
+    protected int getDescriptionResDisabledByAdmin() {
+        return R.string.security_settings_fingerprint_enroll_introduction_message_unlock_disabled;
+    }
+
+    @Override
+    protected Button getCancelButton() {
+        return findViewById(R.id.face_cancel_button);
+    }
+
+    @Override
+    protected Button getNextButton() {
+        return findViewById(R.id.face_next_button);
+    }
+
+    @Override
+    protected TextView getErrorTextView() {
+        return findViewById(R.id.error_text);
+    }
+
+    @Override
+    protected int checkMaxEnrolled() {
+        if (mFaceManager != null) {
+            final int max = getResources().getInteger(
+                    com.android.internal.R.integer.config_faceMaxTemplatesPerUser);
+            final int numEnrolledFaces = mFaceManager.getEnrolledFaces(mUserId).size();
+            if (numEnrolledFaces >= max) {
+                return R.string.face_intro_error_max;
+            }
+        } else {
+            return R.string.face_intro_error_unknown;
+        }
+        return 0;
+    }
+
+    @Override
+    protected long getChallenge() {
+        if (mFaceManager == null) {
+            return 0;
+        }
+        return mFaceManager.preEnroll();
+    }
+
+    @Override
+    protected String getExtraKeyForBiometric() {
+        return ChooseLockSettingsHelper.EXTRA_KEY_FOR_FACE;
+    }
+
+    @Override
+    protected Intent getFindSensorIntent() {
+        return null; // TODO
+    }
+
+    @Override
+    public int getMetricsCategory() {
+        return MetricsProto.MetricsEvent.FACE_ENROLL_INTRO;
+    }
+
+    @Override
+    public void onClick(LinkSpan span) {
+        // TODO(b/110906762)
+    }
+}