This will hurt Linux x64 perf, but we think that's a compiler bug and we're
willing to take the hit for the better clarity of the code sans cast as well as
the better Windows perf. Hopefully eventually the compiler will improve.
BUG=504813
TEST=none
TBR=andrew
Review URL: https://codereview.webrtc.org/1215053002
Cr-Commit-Position: refs/heads/master@{#9516}