StreamSynchronizationTest: Replace class Time with SimulatedClock.
StreamSynchronizationTest: Replace class Time with SimulatedClock.

Remove unused constants and variables.

Bug: none
Change-Id: I7336bbe5bfecbaaf646c9704e4f75532629754d1
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/159944
Reviewed-by: Rasmus Brandt <9545de3a34b925a736ae2b5ee593f3033f743a28@webrtc.org>
Commit-Queue: Åsa Persson <5ff7466874d1fe71d5fe7d79a8a23f5ef50662da@webrtc.org>
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#29826}

TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc