Allocate new AccessorPairs with holes instead of undefined.

Allocate new AccessorPairs with holes instead of undefined.

This is essential for the upcoming map sharing with accessors, and we aleady
have enough machinery to handle the holes now. Furthermore, use "To" template in
2 nearby functions, and made naming a bit more consistent.

In a nutshell: This CL should have no visible effect at all at the moment.
Famous last words...

Committed: https://code.google.com/p/v8/source/detail?r=10919

[Michael Starzinger, 2012-03-05 11:48:05]

LGTM.

https://chromiumcodereview.appspot.com/9594013/diff/1/src/heap.cc
File src/heap.cc (right):

https://chromiumcodereview.appspot.com/9594013/diff/1/src/heap.cc#newcode1933
src/heap.cc:1933: accessors->set_setter(the_hole_value(), SKIP_WRITE_BARRIER);
It would be possible to add an AllocateStructWithFiller() that takes another
initial filler object (besides undefined). This would avoid two unnecessary
writes. But I suppose that's not worth the effort here. So I am fine with
leaving everything as it is.