SetManifestPlaceHolder Problem

Hello, 

I have developed an IntelliJ plugin (Android Studio plugin) that has been working fine but after I update my Gradle to the final version, I got an error on the setManifestPlaceholder that returns no such method Error. I enclosed the code, which I am using to inspect the build.Gradle file.

Module[] modules = ModuleManager.getInstance(myProject).getSortedModules();
Module module = modules[modules.length-2];
GradleBuildModel model = GradleBuildModel.get(module);
assert model != null;
AndroidModel androidModel = model.android();
if (GenerateClassAuthentication.getInstance().isHasCustom()){

    String cutomUrl = GenerateClassAuthentication.getInstance().getCustomURL();
    if (cutomUrl.contains(":") && androidModel!=null){
        cutomUrl = cutomUrl.substring(0, cutomUrl.indexOf(":"));
        androidModel.defaultConfig().setManifestPlaceholder("test",cutomUrl);
    }else  {
        cutomUrl = cutomUrl.substring(0, cutomUrl.indexOf("/"));
        assert androidModel != null;
        androidModel.defaultConfig().setManifestPlaceholder("test", cutomUrl);
    }
}else {
    assert androidModel != null;
    androidModel.defaultConfig().setManifestPlaceholder("test","");
}

Thanks in advance for your help