5/n: Add face settings

This change connects the face status preference controller with the
settings fragment/activity. This change also implements the basic settings
page showing a video, a toggle for keyguard, improve/remove targets,
and footer.

Bug: 111321762

Test: manual
Change-Id: Ifc65f5acbf6551679074df63ef22ffba75229f37

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

@@ -0,0 +1,61 @@
+/*
+ * 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.content.Context;
+import android.content.Intent;
+
+import com.android.settings.R;
+import com.android.settings.core.BasePreferenceController;
+import com.android.settings.utils.AnnotationSpan;
+import com.android.settingslib.HelpUtils;
+import com.android.settingslib.widget.FooterPreference;
+
+import androidx.preference.Preference;
+
+/**
+ * Footer for face settings showing the help text and help link.
+ */
+public class FaceSettingsFooterPreferenceController extends BasePreferenceController {
+
+    private static final String ANNOTATION_URL = "url";
+
+    public FaceSettingsFooterPreferenceController(Context context, String preferenceKey) {
+        super(context, preferenceKey);
+    }
+
+    public FaceSettingsFooterPreferenceController(Context context) {
+        this(context, FooterPreference.KEY_FOOTER);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return AVAILABLE;
+    }
+
+    @Override
+    public void updateState(Preference preference) {
+        super.updateState(preference);
+
+        final Intent helpIntent = HelpUtils.getHelpIntent(
+                mContext, mContext.getString(R.string.help_url_face), getClass().getName());
+        final AnnotationSpan.LinkInfo linkInfo =
+                new AnnotationSpan.LinkInfo(mContext, ANNOTATION_URL, helpIntent);
+        preference.setTitle(AnnotationSpan.linkify(
+                mContext.getText(R.string.security_settings_face_settings_footer), linkInfo));
+    }
+}