Revert of Continue learning for calls in optimized code when we have no type feedback...

Revert of Continue learning for calls in optimized code when we have no type feedback. (patchset #4 id:60001 of https://codereview.chromium.org/868453005/)

Reason for revert:
Serializer tests broke. Need to debug and fix.

Original issue's description:
> Continue learning for calls in optimized code when we have no type feedback.
>
> Based on CL https://codereview.chromium.org/871063002/ which needs to land first.
>
> BUG=
>
> Committed: https://crrev.com/f5f2692b5ff70ac3cd06a903b7846174b97a2e55
> Cr-Commit-Position: refs/heads/master@{#26292}

TBR=verwaest@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=

Review URL: https://codereview.chromium.org/878103002

Cr-Commit-Position: refs/heads/master@{#26293}