IA2 role is not correct for input type button and checkbox with aria role menu as parent

This is continuation of this CL https://codereview.chromium.org/629173002/
Changes were not added in AXRenderObject.cpp

BUG=169574

Review URL: https://codereview.chromium.org/641053003

git-svn-id: svn://svn.chromium.org/blink/trunk@183515 bbb929c8-8fbe-4397-9dbb-9b2b20218538