There was no use for the second temp vector, and the one we
are using is scoped to certain methods, and that scope can be
further restricted.

I'm curious if there is really any value in having the temp
vector instead of allocating a function-scoped local. Will
verify that separately.

Review URL: https://codereview.chromium.org/1533423003

Cr-Commit-Position: refs/heads/master@{#32998}