Companion Device App showing in Settings

Added a feature that users are able to see/remove the apps' associations
in Settings/Connected devices.
It will display the icon of the associations app, app's name and a button
that users are able to remove the associations. Also it will pop up a
dialog alerting user before remove the associations.

Screenshot:
https://screenshot.googleplex.com/APSRhW2retYmAAK

Bug: 165951651
Test: Manually Test

Change-Id: Iccaeaf516e8a78d4ef33415c1c2d7379139ec88c

src/com/android/settings/bluetooth/CompanionAppWidgetPreference.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.bluetooth;
+
+import android.content.Context;
+import android.graphics.drawable.Drawable;
+import android.view.View;
+import android.widget.ImageButton;
+
+import androidx.preference.Preference;
+import androidx.preference.PreferenceViewHolder;
+
+import com.android.settings.R;
+
+/**
+ * A custom preference for companion device apps. Added a button for association removal
+ */
+public class CompanionAppWidgetPreference extends Preference {
+    private Drawable mWidgetIcon;
+    private View.OnClickListener mWidgetListener;
+    private int mImageButtonPadding;
+
+    public CompanionAppWidgetPreference(Drawable widgetIcon, View.OnClickListener widgetListener,
+            Context context) {
+        super(context);
+        mWidgetIcon = widgetIcon;
+        mWidgetListener = widgetListener;
+        mImageButtonPadding = context.getResources().getDimensionPixelSize(
+                R.dimen.bluetooth_companion_app_widget);
+        setWidgetLayoutResource(R.layout.companion_apps_remove_button_widget);
+    }
+
+    @Override
+    public void onBindViewHolder(PreferenceViewHolder holder) {
+        super.onBindViewHolder(holder);
+        ImageButton imageButton = (ImageButton) holder.findViewById(R.id.remove_button);
+        imageButton.setPadding(
+                mImageButtonPadding, mImageButtonPadding, mImageButtonPadding, mImageButtonPadding);
+        imageButton.setColorFilter(getContext().getColor(android.R.color.darker_gray));
+        imageButton.setImageDrawable(mWidgetIcon);
+        imageButton.setOnClickListener(mWidgetListener);
+    }
+
+}