The first is "exact", not "more": qCalculateBlockSize. It ensures that
there's no overflow in multiplying, adding the header size or when
converting back to an int.
The second is the replacement for qAllocMore: it calculates the block
size like the first, but increases the block size to accommodate future
appends. The number of elements that fit in the block is also returned.
Task-number: QTBUG-41230
Change-Id: I52dd43c12685407bb9a6ffff13f5da09f816e667
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
0a78d918f0