the layout changes for the basic IDE ( for the object browser and object
catalog ) seem flacky, I have seen since those changes have been introduced
some strange ( but random ) behaviour ( like the odd unrepeatable core ( maybe
related to this ) and also sometimes Modules appearing in the tree under the
wrong nodes etc. I'm no expert in the basic IDE code but this patch seems to
fix the problem.
However there is one drawback, in the core inducing scenario the tree view
( object catalog ) dissappears, this is because the patch suppresses the
problematic layout in this case ( as the layout seem not to be currently able
to deal with 'no-existent' (recently) deleted current window )
Probably in this scenario a fallback currentwin (instead of nil) could be set
this would behave better but ideally. Ultimately the layout class should
probably be modified ( possibly redesigned )

Change-Id: I9d1e23bd6fc4aae32aa78da8278c318f7051136a