fix incoherency between the wxThread implementation based on MSW threads and pthread: Delete()ing a thread which hasn't started yet must return wxTHREAD_MISC_ERROR

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@64405 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/unix/threadpsx.cpp

@@ -1476,6 +1476,11 @@ wxThreadError wxThread::Delete(ExitCode *rc)
             }
             //else: can't wait for detached threads
     }
+    
+    if (state == STATE_NEW)
+        return wxTHREAD_MISC_ERROR;
+            // for coherency with the MSW implementation, signal the user that 
+            // Delete() was called on a thread which didn't start to run yet.
 
     return wxTHREAD_NO_ERROR;
 }