Fix '-wunused-private-field' warnings generated by new version of
clang.

BUG=chromium:787037
TEST=Successfully built in trybots for caroline, terra and whirlwind.
https://uberchromegw.corp.google.com/i/chromiumos.tryserver/builders/llvm_next_toolchain/builds/916
https://uberchromegw.corp.google.com/i/chromiumos.tryserver/builders/llvm_next_toolchain/builds/917
https://uberchromegw.corp.google.com/i/chromiumos.tryserver/builders/llvm_next_toolchain/builds/918
Also, successfully emerged on falco.

Change-Id: I7adf778c478e7430c3b12b26ed2c8d1d39898d0b
Reviewed-on: https://chromium-review.googlesource.com/779064
Commit-Ready: Caroline Tice <cmtice@chromium.org>
Tested-by: Caroline Tice <cmtice@chromium.org>
Reviewed-by: Sean O'Brien <seobrien@chromium.org>
2 files changed