Fix task id property name.
Fix task id property name.

BUG=skia:6248

Change-Id: I201adb3b66d902cca8a2116aed0490e50c86c207
Reviewed-on: https://skia-review.googlesource.com/8479
Reviewed-by: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>
Commit-Queue: Ben Wagner <3ef7217be91069877d94f7907ce5479000772cd3@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot