AID_SYSTEM_USER - Main thread blocked at getConnectionSummary()

-move getConnectionSummary() to background thread.

Bug: 239394377
Test: atest BluetoothDevicePreferenceTest
Change-Id: I6911f53860ff48ef6a9fa5fe3007c004e6e4a331

src/com/android/settings/bluetooth/BluetoothDevicePreference.java

@@ -27,6 +27,7 @@ import android.graphics.drawable.Drawable;
 import android.os.UserManager;
 import android.text.Html;
 import android.text.TextUtils;
+import android.util.Log;
 import android.util.Pair;
 import android.util.TypedValue;
 import android.view.View;
@@ -41,13 +42,13 @@ import androidx.preference.PreferenceViewHolder;
 import com.android.settings.R;
 import com.android.settings.overlay.FeatureFactory;
 import com.android.settings.widget.GearPreference;
-import com.android.settingslib.bluetooth.BluetoothUtils;
 import com.android.settingslib.bluetooth.CachedBluetoothDevice;
 import com.android.settingslib.core.instrumentation.MetricsFeatureProvider;
 import com.android.settingslib.utils.ThreadUtils;
 
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.util.concurrent.RejectedExecutionException;
 
 /**
  * BluetoothDevicePreference is the preference type used to display each remote
@@ -175,6 +176,7 @@ public final class BluetoothDevicePreference extends GearPreference {
         mHideSecondTarget = hideSecondTarget;
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     void onPreferenceAttributesChanged() {
         Pair<Drawable, String> pair = mCachedDevice.getDrawableWithDescription();
         setIcon(pair.first);
@@ -186,9 +188,15 @@ public final class BluetoothDevicePreference extends GearPreference {
          * any preference info has changed from the previous value.
          */
         setTitle(mCachedDevice.getName());
+        try {
+            ThreadUtils.postOnBackgroundThread(() -> {
+                String summary = mCachedDevice.getConnectionSummary();
                 // Null check is done at the framework
-        setSummary(mCachedDevice.getConnectionSummary());
-
+                ThreadUtils.postOnMainThread(() -> setSummary(summary));
+            });
+        } catch (RejectedExecutionException e) {
+            Log.w(TAG, "Handler thread unavailable, skipping getConnectionSummary!");
+        }
         // Used to gray out the item
         setEnabled(!mCachedDevice.isBusy());