On further reflection, marking the variable proxy at call sites
for foreign functions as a function is ok. Switching this.

Fixed a few IntersectResults that probably should be an explicit set_bounds.

BUG= https://code.google.com/p/v8/issues/detail?id=4203
TEST=test-asm-validator
R=aseemgarg@chromium.org,titzer@chromium.org
LOG=N

Review URL: https://codereview.chromium.org/1656493002

Cr-Commit-Position: refs/heads/master@{#33623}