Non-vectorized KeyedLoadICs used to remember whether they had seen Names
as keys; Crankshaft uses this information to avoid emitting elements
accesses which would always deopt. This CL restores that functionality
for vector ICs.

BUG=chromium:594183
LOG=y
R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/1912593002

Cr-Commit-Position: refs/heads/master@{#35706}