DynamicBuffer_v2: Shrink the underlying memory by
the specified number of bytes.
Erases n bytes from the
end of the vector by resizing the vector object. If n
is greater than the current size of the vector, the vector is emptied.
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)