Remove unused CookiePreferences from report sender and never send cookies

All non-test callers of ReportSender use CookiePreferences::DO_NOT_SEND_COOKIES.
Remove the enum altogether.

BUG=716098

Review-Url: https://codereview.chromium.org/2851493003
Cr-Original-Commit-Position: refs/heads/master@{#468150}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 49c44f6ba26559359103400eb2480a832955d71f
3 files changed