Setting accessibilityLabel on the NSScrollView wrappers turned them into
leaf elements, so VoiceOver never descended into the document views
(NSOutlineView/NSTableView/NSTextView) inside. Tab still worked because
the key-view loop is independent of the accessibility tree.
Also removed the redundant setAccessibilityRole calls on the document
views — they already default to those roles, and re-setting the same
role can interfere with the view's custom a11y implementation.
Matches the pattern already used in ConnectWindowController, whose
server table VoiceOver reaches correctly.
Talon
c684824b10