Fix crash when no Bluetooth feature in Settings

- Move PreferenceGroup init method out of isAvailable() condition,
  then PreferenceGroup will not be null.
- Update getAvailabilityStatus(), since the controller now may have usb
  and dock.

Bug: 110712414
Test: make -j42 RunSettingsRoboTests
Change-Id: I4d85a42c26fb20d319e7321177b271933be3fdb0

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

@@ -109,6 +109,10 @@ public abstract class BluetoothDeviceUpdater implements BluetoothCallback,
      * Force to update the list of bluetooth devices
      */
     public void forceUpdate() {
+        if (mLocalManager == null) {
+            Log.e(TAG, "forceUpdate() Bluetooth is not supported on this device");
+            return;
+        }
         if (BluetoothAdapter.getDefaultAdapter().isEnabled()) {
             final Collection<CachedBluetoothDevice> cachedDevices =
                     mLocalManager.getCachedDeviceManager().getCachedDevicesCopy();
@@ -119,6 +123,10 @@ public abstract class BluetoothDeviceUpdater implements BluetoothCallback,
     }
 
     public void removeAllDevicesFromPreference() {
+        if (mLocalManager == null) {
+            Log.e(TAG, "removeAllDevicesFromPreference() BT is not supported on this device");
+            return;
+        }
         final Collection<CachedBluetoothDevice> cachedDevices =
                 mLocalManager.getCachedDeviceManager().getCachedDevicesCopy();
         for (CachedBluetoothDevice cachedBluetoothDevice : cachedDevices) {