We have a bottleneck around storing elements in the array and object prototypes,
but the Push() and Unshift() builtins don't respect them.

Fix this exactly to the level of existing support for stores.

BUG=v8:4043
LOG=N
NOTRY=true

Review URL: https://codereview.chromium.org/1066003003

Cr-Commit-Position: refs/heads/master@{#27943}