The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/c4d63f5f180a99b53874d548f7186e0181805f57

commit c4d63f5f180a99b53874d548f7186e0181805f57
Author: Peter K. Lee <pkl@chromium.org>
Date: Tue Mar 13 21:43:02 2018

Remove kShareCanonicalURL experiment flag.

Feature was launched in M64.

Bug:  820975 
Cq-Include-Trybots: master.tryserver.chromium.mac:ios-simulator-cronet;master.tryserver.chromium.mac:ios-simulator-full-configs
Change-Id: Ie8deeda24708509caafde53a3a908bbe1ee84376
Reviewed-on: https://chromium-review.googlesource.com/959041
Reviewed-by: Justin Cohen <justincohen@chromium.org>
Commit-Queue: Peter Lee <pkl@chromium.org>
Cr-Commit-Position: refs/heads/master@{#542923}
[modify] https://crrev.com/c4d63f5f180a99b53874d548f7186e0181805f57/ios/chrome/browser/BUILD.gn
[modify] https://crrev.com/c4d63f5f180a99b53874d548f7186e0181805f57/ios/chrome/browser/about_flags.mm
[modify] https://crrev.com/c4d63f5f180a99b53874d548f7186e0181805f57/ios/chrome/browser/ios_chrome_flag_descriptions.cc
[modify] https://crrev.com/c4d63f5f180a99b53874d548f7186e0181805f57/ios/chrome/browser/ios_chrome_flag_descriptions.h
[modify] https://crrev.com/c4d63f5f180a99b53874d548f7186e0181805f57/ios/chrome/browser/ui/activity_services/BUILD.gn
[modify] https://crrev.com/c4d63f5f180a99b53874d548f7186e0181805f57/ios/chrome/browser/ui/activity_services/activity_service_legacy_coordinator.mm
[delete] https://crrev.com/88e78b4b7be97c04c92ed66d5393781e1adb08ce/ios/chrome/browser/ui/activity_services/canonical_url_feature.cc
[delete] https://crrev.com/88e78b4b7be97c04c92ed66d5393781e1adb08ce/ios/chrome/browser/ui/activity_services/canonical_url_feature.h