Cordova Build Error ..Defaul target android-25 I am changed to android-19 ..BUILD ERROR

I am changing the properties android-25 to android-19 following files

C:\xampp\htdocs\ionic\Demo\platforms\android\project.properties.xml
C:\xampp\htdocs\ionic\Demo\platforms\android\Android_manifest.xml
C:\xampp\htdocs\ionic\Demo\platforms\android\CordovaLib\Project_properties.xml

then i am execute ionic build cordova

show the following error

@TargetApi(Build.VERSION_CODES.LOLLIPOP)
                                  ^
  symbol:   variable LOLLIPOP
  location: class VERSION_CODES
C:\xampp\htdocs\ionic\Demo\platforms\android\CordovaLib\src\org\apache\cordova\engine\SystemWebChromeClient.java:262: error: cannot find symbol
    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
                              ^