Remove an unused function after https://codereview.chromium.org/1581473002
Remove an unused function after https://codereview.chromium.org/1581473002

Found by clang/win.

BUG=82385
TBR=scottmg

Review URL: https://codereview.chromium.org/1585703002 .

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#369205}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk