`nsIControllerContext` isn't implemented with JS even in comm-central nor
BlueGriffon. Therefore, it can be a builtinclass.
Additionally, it's `init()` returns always `NS_OK`, and always called with
`null` from JS, and always called with an instance from C++. So that its the
only implementation, `nsBaseCommandController` can have 2 constructors which
does what `Init()` currently does.
Differential Revision: https://phabricator.services.mozilla.com/D25728
`nsIControllerCommandTable` isn't implemented with JS even in comm-central nor
BlueGriffon. Therefore, we can make it a builtinclass.
Additionally, it's inherited only by nsControllerCommandTable. So, all users
in C++ can treat the concrete class directly.
Differential Revision: https://phabricator.services.mozilla.com/D25727
Jorg K