#i123795# add a windowForParent() method for AquaA11yWrapper

for getting the parent window of an A11y enabled NSView. The method
viewElementForParent() was abused for that purpose, but it was mis-named
and mis-typed. The new method cleans this up and the now unused
viewElementForParent() method can be retired.
#i114728# set AOO's Mac baseline to OSX 10.7
#i123795# amend r1565258's commit with its missing part