This plugin provides a minor extension to the ADT plugin to support XML formatting via the "Source > Format" action on files. The reason the plugin package name starts with the word "overlay" instead of the normal "com.android.eclipse" package is that the plugin name *must* be alphabetically later than "org.eclipse". The reasons for this is detailed in issue http://code.google.com/p/android/issues/detail?id=20450 but essentially the plugin registration to override the formatProcessor is processed in the alphabetical order of the plugin names, so the org.eclipse plugin would clobber the com.android.eclipse plugin. To work around this, the specific registration code was moved out to a separate plugin, but the formatter itself continues to live in ADT.