Split battery header text to a separated preference

This is a no-op refactor. This change makes the Catalyst migration of battery level bar easy.

Bug: 372774754
Test: manual
Flag: EXEMPT bug fix
Change-Id: I6e64e6d9b34aeca584f4d4e951c58c3e1b361f9d

src/com/android/settings/fuelgauge/BatteryHeaderTextPreference.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2024 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.fuelgauge;
+
+import android.content.Context;
+import android.text.TextUtils;
+import android.util.AttributeSet;
+import android.widget.TextView;
+
+import androidx.annotation.Nullable;
+import androidx.preference.Preference;
+import androidx.preference.PreferenceViewHolder;
+
+import com.android.settings.R;
+
+/** A preference for battery header text. */
+public class BatteryHeaderTextPreference extends Preference {
+    private static final String TAG = "BatteryHeaderTextPreference";
+
+    @Nullable private CharSequence mText;
+    @Nullable private CharSequence mContentDescription;
+
+    public BatteryHeaderTextPreference(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        setLayoutResource(R.layout.preference_battery_header_text);
+    }
+
+    @Override
+    public void onBindViewHolder(PreferenceViewHolder view) {
+        final TextView textView = (TextView) view.findViewById(R.id.text);
+        textView.setText(mText);
+        if (!TextUtils.isEmpty(mContentDescription)) {
+            textView.setContentDescription(mContentDescription);
+        }
+    }
+
+    void setText(@Nullable CharSequence text) {
+        mText = text;
+        notifyChanged();
+    }
+
+    void setContentDescription(@Nullable CharSequence contentDescription) {
+        mContentDescription = contentDescription;
+        notifyChanged();
+    }
+}