Define step timing function for the cc animation framework.

cc/blink/web_filter_animation_curve_impl.cc

 // Copyright 2014 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 "cc/blink/web_filter_animation_curve_impl.h"
 
 #include "cc/animation/keyframed_animation_curve.h"
 #include "cc/animation/timing_function.h"
 #include "cc/blink/web_animation_curve_common.h"
 #include "cc/blink/web_filter_operations_impl.h"
@@ skipping 31 matching lines @@
                                       double x2,
                                       double y2) {
   const cc::FilterOperations& filter_operations =
       static_cast<const WebFilterOperationsImpl&>(keyframe.value())
           .AsFilterOperations();
   curve_->AddKeyframe(cc::FilterKeyframe::Create(
       base::TimeDelta::FromSecondsD(keyframe.time()), filter_operations,
       cc::CubicBezierTimingFunction::Create(x1, y1, x2, y2)));
 }
 
+void WebFilterAnimationCurveImpl::add(const WebFilterKeyframe& keyframe,
+                                      int steps,
+                                      float steps_start_offset) {
+  const cc::FilterOperations& filter_operations =
+      static_cast<const WebFilterOperationsImpl&>(keyframe.value())
+          .AsFilterOperations();
+  curve_->AddKeyframe(cc::FilterKeyframe::Create(
+      base::TimeDelta::FromSecondsD(keyframe.time()), filter_operations,
+      cc::StepsTimingFunction::Create(steps, steps_start_offset)));
+}
+
 void WebFilterAnimationCurveImpl::setTimingFunction(TimingFunctionType type) {
   curve_->SetTimingFunction(CreateTimingFunction(type));
 }
 
 void WebFilterAnimationCurveImpl::setTimingFunction(double x1,
                                                     double y1,
                                                     double x2,
                                                     double y2) {
   curve_->SetTimingFunction(
       cc::CubicBezierTimingFunction::Create(x1, y1, x2, y2).Pass());
 }
 
 scoped_ptr<cc::AnimationCurve>
 WebFilterAnimationCurveImpl::CloneToAnimationCurve() const {
   return curve_->Clone();
 }
 
 }  // namespace cc_blink