[runtime] Initial step towards switching Execution::Call to callable.

[runtime] Initial step towards switching Execution::Call to callable.

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.

CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux_nosnap_dbg
R=jarin@chromium.org
BUG=v8:4413
LOG=n

Review URL: https://codereview.chromium.org/1353723002

Cr-Commit-Position: refs/heads/master@{#30791}