Revert of Optimize for TouchStart responsiveness

components/scheduler/renderer/task_cost_estimator.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/scheduler/renderer/task_cost_estimator.h"
 
 namespace scheduler {
 
 TaskCostEstimator::TaskCostEstimator(int sample_count,
                                      double estimation_percentile)
@@ skipping 17 matching lines @@
     // TODO(skyostil): Should we do this less often?
     expected_task_duration_ =
         rolling_time_delta_history_.Percentile(estimation_percentile_);
   }
 }
 
 base::TimeTicks TaskCostEstimator::Now() {
   return base::TimeTicks::Now();
 }
 
-void TaskCostEstimator::Clear() {
-  rolling_time_delta_history_.Clear();
-  expected_task_duration_ = base::TimeDelta();
-}
-
 }  // namespace scheduler