Bridge old-style ArrayHandle to new-style
The new-style ArrayHandle
uses Buffer
objects to manage data. Thus,
when one is decorating the other, it expects to find the Buffer
objects, which the old-style ArrayHandle
s do not have. To make the two
work together, fake buffers in the old-style arrays.
The buffers in old-style arrays are empty, but have metadata that points back to the `ArrayHandle.
This change will allow us to update the rest of the ArrayHandle
s to the
new style one at a time. The dependencies will not matter. Thus, we can
keep smaller MRs.