Add AX attribute for input type

When Input type is url, tel, search and email,
AX attributes for them will be exposed.

BUG=323161

Review URL: https://codereview.chromium.org/596393004

git-svn-id: svn://svn.chromium.org/blink/trunk@183119 bbb929c8-8fbe-4397-9dbb-9b2b20218538