Add feature flag for connected device

Add feature flag to toggle connected device between new and old
feature.

ConnectedDeviceDashboardFragment will contain new feature will
ConnectedDeviceDashboardFragment2 will hold old feature.

Bug: 69333961
Test: Build
Change-Id: I0ea932c69dea5242129aab994d5142b1f87fbea0

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

@@ -14,4 +14,4 @@ public class BluetoothFeatureProviderImpl implements BluetoothFeatureProvider {
     public boolean isDeviceDetailPageEnabled() {
         return false;
     }
-}
+}