This reverts commit 26fdb617.

Reason for revert: v8:6378

Original change's description:
> [stubs] Properly convert the receiver for GetPropertyStub.
> 
> Call ToObject on the GetPropertyStub input first, so that lookups on
> Strings and other primitives don't automatically hit the runtime, i.e.
> as the stub is also used to lookup the special @@split and @@replace
> symbols for various String builtins.
> 
> BUG=v8:5269
> R=​ishell@chromium.org
> 
> Change-Id: I5dbbc84aa2051173bf10be71c782fbe448481034
> Reviewed-on: https://chromium-review.googlesource.com/488441
> Commit-Queue: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#44961}

TBR=ishell@chromium.org,bmeurer@chromium.org
# Not skipping CQ checks because original CL landed > 1 day ago.
BUG=v8:5269

Change-Id: I1e2e83b492d82656ead81ea35adbbcf5d324d2b8
Reviewed-on: https://chromium-review.googlesource.com/500135Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45206}