bake constants into the traced graph, get rid of getNestedValueTrace (#21046)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/21046
ghimport-source-id: 5cb3efb1896fbe42336e24c14fbf0bb5e646528e
Differential Revision: D15530991
Pulled By: wanchaol
fbshipit-source-id: b096ca5a1cdce496742b7f7e1de3ef8d21e9a8b0
