Unskip text tests after harfbuzz rollback

Unskip complex text tests failures caused by harfbuzz upgrade as the
harfbuzz version has been rolled back.

BUG=353015
TBR=wangxianzhu@chromium.org

Review URL: https://codereview.chromium.org/202153004

git-svn-id: svn://svn.chromium.org/blink/trunk@169417 bbb929c8-8fbe-4397-9dbb-9b2b20218538