Roll src/third_party/icu dd72764:866ff69 (svn 292996:293126)

Summary of changes available at:
https://chromium.googlesource.com/chromium/deps/icu52/+log/dd72764..866ff69

BUG=433866
TEST=see the bug
TBR=mbarbella@chromium.org

Review URL: https://codereview.chromium.org/724233004

Cr-Commit-Position: refs/heads/master@{#305849}