port d5bbd45f (r30808).

oringial commit message:

    Currently Execution::Call (and friends) still duplicate a lot of the
    Call sequence logic that should be encapsulated in the Call and
    CallFunction builtins. So the plan now is to switch Execution::Call
    to accept any Callable and just pass that through to the Call builtin.

BUG=

Review URL: https://codereview.chromium.org/1350183005

Cr-Commit-Position: refs/heads/master@{#30828}