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 classes7;

class C
{
    int i=0;
    void f()
    {
        i=42;
    }
    void g()
    {
        f();
    }
}

void main()
{
    scope c = new C;
    c.g();
    assert(c.i == 42);
}