With IE11 no longer supported, the primary problem with assistive technology support for native HTML5 elements no longer applies.
This commit removes the `role` attribute from the following HTML5 elements with default landmark roles, per formerly required role attributes and W3C.
Follow-up to [17669], [21261], [23452], [24832], [29892], [38833], [40851], [43842], [46271], [49216].
Props costdev, craigfrancis, joedolson, mukesh27, ryokuhi, sabernhardt.
Fixes#54079.
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git-svn-id: http://core.svn.wordpress.org/trunk@51604 1a063a9b-81f0-0310-95a4-ce76da25c4cd
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