In Writer/OOoBasic, when using the Transferable framework to copy-and-paste
between two documents, and the transferable is 'empty', the application crashes.

STEPS TO REPRODUCE THE PROBLEM
1. Create a new document, and create a new Basic module Module1 with default sub
Main
2. In Main, enter the following code:
Dim oTransferable As Object
Dim oNewDoc       As Object
Dim aNoArgs()
oTransferable = ThisComponent.CurrentController.getTransferable() ' ***
oNewDoc = StarDesktop.loadComponentFromURL("private:factory/swriter", "_blank",
0, aNoArgs())
oNewDoc.CurrentController.insertTransferable(oTransferable)

*** Since this document is currently empty, no selection has been made, and
oTransferable contains nothing (but note an object has still been returned, this
is not Empty, Null, or Missing)

3. Run Main, and the application will pause for a second, then system crash.

POSSIBLE WORKAROUNDS
Could avoid this by checking that something has actually been selected in the
current document before invoking this code.

PROPOSED SOLUTION
insertTransferable(obj) should just do nothing in the case where the
Transferable obj contains nothing; and possibly also that getTransferable()
should return a null object (not sure if that is possible?) that can be tested
for Null or Empty.