wxGUI: fix loading workspace on Windows when workspace was saved when map window is minimized (merged from trunk, https://trac.osgeo.org/grass/changeset/66586)

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@66626 15284696-431f-4ddb-bdfa-cd5b030d7da7

gui/wxpython/core/workspace.py

@@ -124,6 +124,11 @@ class ProcessWorkspaceFile:
                 except:
                     pos  = None
                     size = None
+                # this happens on Windows when mapwindow is minimized when saving workspace
+                else:
+                    if posVal[0] == -32000:
+                        pos = None
+                        size = None
             else:
                 pos  = None
                 size = None