This fixes a corner-case where the call reduction of the aforementioned
getter did not simulate the {ToObject} conversion of the receiver value
as required by the spec. This caused the wrong prototype to be constant
promoted (i.e. {null} instead of wrapper object prototype).

R=jarin@chromium.org
TEST=mjsunit/regress/regress-crbug-694709
BUG=chromium:694709

Change-Id: Idf3a37071949d9ddaf5ef43974570c06fd31c0c9
Reviewed-on: https://chromium-review.googlesource.com/445818Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43376}