Clean up and modernize the feedback code

BUG=634518
TEST=Tests should keep passing.

Review-Url: https://codereview.chromium.org/2217163003
Cr-Original-Commit-Position: refs/heads/master@{#410223}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 7945509958001242f8d26cf3b6d3d4e5596f52c8
5 files changed