port 56d90782 (r36597)

  original commit message:
  In Crankshaft, we would install special ICs that didn't need a vector and slot
  in the MEGAMORPHIC case. This optimization limits our hand against future
  improvements.

BUG=

Review-Url: https://codereview.chromium.org/2030303002
Cr-Commit-Position: refs/heads/master@{#36700}