title: Flutter unresolved package in Android Manifest com.apptreesoftware.barcodescan
body: <p>I'm trying to set up a QR code scanner in my app following directions online, but for some reason when i add 
  <code>&lt;activity android:name="com.apptreesoftware.barcodescan.BarcodeScannerActivity"/&gt;</code>
  it gives me unresolved package error. Not sure why since i added <code>barcode_scan ^0.0.4</code> to my yaml file. </p>