We lost the print functionality for stub schedules somewhere on the
way. This re-adds the appropriate call to TraceSchedule to get it
going again.

Bug: v8:7327
Change-Id: I245823b440542708410d2253f9f4e78b2e22f3c9
Reviewed-on: https://chromium-review.googlesource.com/1047270Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53038}