title: Why do the Android docs say intent extras need package prefix
body: <p>According to the Android docs Intent extra name must have a package prefix. I've been using Intent extra names without prefixes for a long time and it seems like there is no chance of collision since what really matters is the Intent action being unique. So are the docs just wrong or am I missing something?</p>
  
  <p>The docs for <a href="http://developer.android.com/reference/android/content/Intent.html#putExtra%28java.lang.String,%20boolean%29" rel="noreferrer">putExtra</a> say:</p>
  
  <p>Add extended data to the intent. The name must include a package prefix, for example the app com.android.contacts would use names like "com.android.contacts.ShowAll".</p>