GAE project to android error?

I have a google appengine project in my eclipse workplace. Also I have android development toolkit installed in eclipse and by mistake I clicked Android_Tools > Convert_to_Android_Project The console show the following error :

Project has no default.properties file! Edit the project properties to set one.

I checked 开发者_运维技巧the properties of the project and they are same as that of any other GAE project. How do I undo this to get back the original project properties?