port 09255541 (r41135)

  original commit message:
  This removes the deprecated generator support for resumable functions
  from {FullCodeGenerator}. The existing {AstNumbering} heuristic already
  triggers Ignition for most resumable functions, with this change we make
  said heuristic a hard choice and remove the deprecated code. This also
  has the advantage that any suspended {JSGeneratorObject} instance on the
  heap is guaranteed to have code based on a bytecode array.

BUG=

Review-Url: https://codereview.chromium.org/2522653003
Cr-Commit-Position: refs/heads/master@{#41204}