Clean up: use AppPreference for PowerGaugePreference

- And remove the code for customizing app icon size.

Bug: 65182905
Bug: 68426851
Test: robotests
Change-Id: I4e37bbee3636266f7c1a639b8e9faabb78d61110

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

@@ -19,15 +19,13 @@ package com.android.settings.fuelgauge;
 import android.content.Context;
 import android.graphics.drawable.ColorDrawable;
 import android.graphics.drawable.Drawable;
-import android.support.v7.preference.Preference;
 import android.support.v7.preference.PreferenceViewHolder;
 import android.util.AttributeSet;
-import android.widget.ImageView;
-import android.widget.LinearLayout;
 import android.widget.TextView;
 
 import com.android.settings.R;
 import com.android.settings.Utils;
+import com.android.settings.widget.AppPreference;
 
 /**
  * Custom preference for displaying battery usage info as a bar and an icon on
@@ -36,8 +34,7 @@ import com.android.settings.Utils;
  * The battery usage info could be usage percentage or usage time. The preference
  * won't show any icon if it is null.
  */
-public class PowerGaugePreference extends Preference {
+public class PowerGaugePreference extends AppPreference {
-    private final int mIconSize;
 
     private BatteryEntry mInfo;
     private CharSequence mContentDescription;
@@ -64,7 +61,6 @@ public class PowerGaugePreference extends Preference {
         setWidgetLayoutResource(R.layout.preference_widget_summary);
         mInfo = info;
         mContentDescription = contentDescription;
-        mIconSize = context.getResources().getDimensionPixelSize(R.dimen.app_icon_size);
         mShowAnomalyIcon = false;
     }
 
@@ -107,8 +103,6 @@ public class PowerGaugePreference extends Preference {
     @Override
     public void onBindViewHolder(PreferenceViewHolder view) {
         super.onBindViewHolder(view);
-        ImageView icon = (ImageView) view.findViewById(android.R.id.icon);
-        icon.setLayoutParams(new LinearLayout.LayoutParams(mIconSize, mIconSize));
 
         final TextView subtitle = (TextView) view.findViewById(R.id.widget_summary);
         subtitle.setText(mProgress);

tests/robotests/src/com/android/settings/fuelgauge/PowerGaugePreferenceTest.java

@@ -15,6 +15,8 @@
  */
 package com.android.settings.fuelgauge;
 
+import static com.google.common.truth.Truth.assertThat;
+
 import android.content.Context;
 import android.graphics.drawable.Drawable;
 import android.graphics.drawable.VectorDrawable;
@@ -35,8 +37,6 @@ import org.mockito.MockitoAnnotations;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.Config;
 
-import static com.google.common.truth.Truth.assertThat;
-
 @RunWith(SettingsRobolectricTestRunner.class)
 @Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION)
 public class PowerGaugePreferenceTest {
@@ -53,7 +53,7 @@ public class PowerGaugePreferenceTest {
         MockitoAnnotations.initMocks(this);
 
         mContext = RuntimeEnvironment.application;
-        mRootView = LayoutInflater.from(mContext).inflate(R.layout.preference,
+        mRootView = LayoutInflater.from(mContext).inflate(R.layout.preference_app,
                 null);
         mWidgetView = LayoutInflater.from(mContext).inflate(R.layout.preference_widget_summary,
                 null);
@@ -61,6 +61,7 @@ public class PowerGaugePreferenceTest {
         mPreferenceViewHolder = PreferenceViewHolder.createInstanceForTests(mRootView);
 
         mPowerGaugePreference = new PowerGaugePreference(mContext);
+        assertThat(mPowerGaugePreference.getLayoutResource()).isEqualTo(R.layout.preference_app);
     }
 
     @Test