Fixed a critical bug in the runtime, where _d_allocmemoryT would mark the memory block as having pointers (for scanning) opposite of what it should. So pointers would not be seen and freed. Should fix a bunch of regressions with AAs.

module bug19;

void main()
{
    auto dg = (int i) { return i*2; };
    assert(dg(2) == 4);
}