RFR: JDK-8186466: Fix accessibility and other minor issues in java.base

[Martin Buchholz]

I don't know how hard it would be to make the header rows in BlockingDeque
presented like the ones in e.g. Deque.
Deque uses striped thead, which gets the #DDD background from the
stylesheet.  And having <thead>s is probably itself an accessibility
feature.

table.striped > thead {
    background-color: #DDD;
    border: 1px solid black;
}

we could brute force the same background color or try to convert these to
striped tables (but you probably tried that).