Updates CloneIC builtin to take the CloneIC_slow path when there is no
feedback vector. Also fixes the CloneIC_Slow to handle proxies correctly.

StoreInArrayLiteralIC doesn't change the behaviour but just makes it
consistent with other ICs.

Bug: v8:8293
Change-Id: Ib824b3ef06db1595ce06f04669857bb957cbe072
Reviewed-on: https://chromium-review.googlesource.com/c/1475750
Commit-Queue: Mythri Alle <mythria@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59682}