Reviewed by Oliver Hunt.

        Removed a use of markDOMObjectWrapper: ActiveDOMObjects, Workers, and MessagePorts
        https://bugs.webkit.org/show_bug.cgi?id=59333

        * WebCore.xcodeproj/project.pbxproj: Added .idl files for easier editing.

        * bindings/js/JSDOMBinding.cpp:
        * bindings/js/JSDOMBinding.h:
        * bindings/js/JSDocumentCustom.cpp:
        * bindings/js/JSWorkerContextCustom.cpp:
        (WebCore::JSWorkerContext::visitChildren): Removed now-unused functions.

        * bindings/scripts/CodeGeneratorJS.pm: Added support for ActiveDOMObject
        lifetime management.

        * dom/Document.idl: No need for a custom mark function anymore, since
        ActiveDOMObjets now manage their own lifetimes.

        * dom/MessagePort.cpp:
        (WebCore::MessagePort::hasPendingActivity): Correctly report that we
        have pending activity when we're remotely entangled, instead of relying
        on our clients to know this about us and do the check for us.

        * dom/MessagePort.h: FIXME!

        * dom/MessagePort.idl:
        * fileapi/DOMFileSystem.idl:
        * fileapi/FileReader.idl:
        * fileapi/FileWriter.idl:
        * notifications/Notification.idl:
        * notifications/NotificationCenter.idl:
        * page/EventSource.idl:
        * storage/IDBDatabase.idl:
        * storage/IDBRequest.idl:
        * storage/IDBTransaction.idl:
        * webaudio/AudioContext.idl:
        * websockets/WebSocket.idl:
        * workers/AbstractWorker.idl:
        * workers/SharedWorker.idl:
        * workers/Worker.idl: Opt in to ActiveDOMObject lifetime management.

        * workers/WorkerContext.cpp:
        (WebCore::WorkerContext::hasPendingActivity): No need to make up for
        MessagePort::hasPendingActivity being wrong anymore, since it's now right.

        * xml/XMLHttpRequest.idl: Opt in to ActiveDOMObject lifetime management.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@84789 268f45cc-cd09-0410-ab3c-d52691b4dbfc