This interface is provided to scripts, and provides a means of access to
the various interfaces which they might need to perform some action on
a document. It is required to be passed as the first argument for any
Java scripts.
provides access to the context where the script was invoked
In some cases, it is possible that scripts, embedded in a document,
are executed from within a context which is not the document
itself. In this case, the getInvocationContext member allows
to access this context.
Note that the returned context is allowed to be NULL, in this case,
the document as returned by getDocument is the invocation context.
If the returned context is not NULL, its ScriptContainer attribute
equals the document as returned by XScriptContext::getDocument.