[Material Next] Update accessibility tool footer style

1. Implement API extends Material Next FooterBarPreference and support Accessibility API for icons
2. Apply solutions to accessibility tools and framework tools in
accessibility settings page.
3. Apply DashboardFragment for Caption preference for xml parser

Bug: 185973304
Test: make RunSettingsRoboTests -j52
Change-Id: I6b80bc80190d6666e3fbcd462442a9f2c0e60bba

src/com/android/settings/accessibility/AccessibilityFooterPreferenceController.java

@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2021 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.accessibility;
+
+import android.content.Context;
+
+import androidx.preference.PreferenceScreen;
+
+import com.android.settings.R;
+import com.android.settings.core.BasePreferenceController;
+
+/**
+ * Base class for accessibility preference footer.
+ */
+public abstract class AccessibilityFooterPreferenceController extends BasePreferenceController {
+
+    public AccessibilityFooterPreferenceController(Context context, String key) {
+        super(context, key);
+    }
+
+    @Override
+    public int getAvailabilityStatus() {
+        return AVAILABLE;
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+
+        final AccessibilityFooterPreference footerPreference =
+                screen.findPreference(getPreferenceKey());
+        updateFooterPreferences(footerPreference);
+    }
+
+
+    /** Returns the accessibility feature name. */
+    protected abstract String getLabelName();
+
+    private void updateFooterPreferences(AccessibilityFooterPreference footerPreference) {
+        final String iconContentDescription = mContext.getString(
+                R.string.accessibility_introduction_title, getLabelName());
+        footerPreference.setIconContentDescription(iconContentDescription);
+    }
+}