This reverts commit ec619cbd.

Reason for revert: Crashing on Canary
BUG=chromium:718891

Original change's description:
> [Interpreter] Transition JSFunctions to call optimized code when possible.
> 
> Now that the optimized code hangs off the feedback vector, it is possible
> to check whether a function has optimized code available every time it's
> called in the interpreter entry trampoline. If optimized code exists, the
> interpreter entry trampoline 'self-heals' the closure to point to the
> optimized code and links the closure into the optimized code list.
> 
> BUG=v8:6246
> 
> Change-Id: If1bd7c555bb0551bfe04b36baa6bcf949604717e
> Reviewed-on: https://chromium-review.googlesource.com/488026
> Reviewed-by: Michael Stanton <mvstanton@chromium.org>
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#45103}

TBR=rmcilroy@chromium.org,mvstanton@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
BUG=v8:6246

Change-Id: Ibda719be90fddf1d116c03a2a0c3018bcbe76018
Reviewed-on: https://chromium-review.googlesource.com/498632Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45169}