Speculatively fix another bug involving deleting invalid handles.

If this handle is deleted, make sure to mark it as such.  Otherwise,
there seems to be a double delete occuring and causing issues.


git-svn-id: https://groke.mcmaster.ca/svn/grad/colin/trunk/TableTool@8511 57e6efec-57d4-0310-aeb1-a6c144bb1a8b

@GUI/close_fig.m

@@ -12,6 +12,7 @@
 function [] = close_fig(object,src,event)
 if (object.validation_report_handle ~= 0)
     delete(object.validation_report_handle);
+    object.validation_report_handle = 0;
 end
 object.save_data;
 object.Data.open = 0;

@GUI/cvc_ext_call.m

@@ -7,6 +7,7 @@ object.save_call([],[]);
 object.save_data;
 if (object.validation_report_handle ~= 0)
     delete(object.validation_report_handle);
+    object.validation_report_handle = 0;
 end
 error = object.check_call([],2);
 

@GUI/pvs_ext_call.m

@@ -13,6 +13,7 @@ object.save_call([],[]);
 object.save_data;
 if (object.validation_report_handle ~= 0)
     delete(object.validation_report_handle);
+    object.validation_report_handle = 0;
 end
 error = object.check_call([],2);