Update MotionPredictorBenchmark.

* Use realistic durations and moving events to ensure the model is
  fully exercised.
* The requested prediction time is only a target, and it is valid for
  predictions to fall short of it.

com.android.perftests.core (2 Tests)
[1/2] android.input.MotionPredictorBenchmark#timeRecordAndPredict: PASSED (8.392s)
	perfetto_file_path: /sdcard/test_results/android.input.MotionPredictorBenchmark_timeRecordAndPredict/PerfettoListener/perfetto_android.input.MotionPredictorBenchmark_timeRecordAndPredict-1.perfetto-trace
	timeRecordAndPredict_mean (ns): 84059
	timeRecordAndPredict_median (ns): 82093
	timeRecordAndPredict_min (ns): 77361
	timeRecordAndPredict_standardDeviation: 5402
[2/2] android.input.MotionPredictorBenchmark#timeCreatePredictor: PASSED (7.650s)
	perfetto_file_path: /sdcard/test_results/android.input.MotionPredictorBenchmark_timeCreatePredictor/PerfettoListener/perfetto_android.input.MotionPredictorBenchmark_timeCreatePredictor-1.perfetto-trace
	timeCreatePredictor_mean (ns): 104809
	timeCreatePredictor_median (ns): 105000
	timeCreatePredictor_min (ns): 101148
	timeCreatePredictor_standardDeviation: 2837

Bug: 167946763
Test: atest MotionPredictorBenchmark
Change-Id: I2861a2f377a34eff6571a6ecdc4a34c46fcd753b