Add preferences in new connected device page

1. Add device preference
2. connection preference

This cl add click action for Add device preference. Action for
connection preference will be added in future cl.

Bug: 69333961
Test: Screenshot | RunSettingsRoboTests
Change-Id: Ifb1afc8371ee45165ea22a7a195a774ba04fdeea

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

@@ -73,10 +73,20 @@ public class BluetoothPairingDetail extends DeviceListPreferenceFragment impleme
     public void onStart() {
         super.onStart();
 
-        updateContent(mLocalAdapter.getBluetoothState());
+        updateBluetooth();
         mAvailableDevicesCategory.setProgress(mLocalAdapter.isDiscovering());
     }
 
+    @VisibleForTesting
+    void updateBluetooth() {
+        if (mLocalAdapter.isEnabled()) {
+            updateContent(mLocalAdapter.getBluetoothState());
+        } else {
+            // Turn on bluetooth if it is disabled
+            mLocalAdapter.enable();
+        }
+    }
+
     @Override
     public void onStop() {
         super.onStop();