Define step timing function for the cc animation framework.

cc/blink/web_transform_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_transform_animation_curve_impl.h"
 
 #include "cc/animation/keyframed_animation_curve.h"
 #include "cc/animation/timing_function.h"
 #include "cc/animation/transform_operations.h"
 #include "cc/blink/web_animation_curve_common.h"
@@ skipping 35 matching lines @@
                                          double x2,
                                          double y2) {
   const cc::TransformOperations& transform_operations =
       static_cast<const WebTransformOperationsImpl&>(keyframe.value())
           .AsTransformOperations();
   curve_->AddKeyframe(cc::TransformKeyframe::Create(
       base::TimeDelta::FromSecondsD(keyframe.time()), transform_operations,
       cc::CubicBezierTimingFunction::Create(x1, y1, x2, y2)));
 }
 
+void WebTransformAnimationCurveImpl::add(const WebTransformKeyframe& keyframe,
+                                         int steps,
+                                         float steps_start_offset) {
+  const cc::TransformOperations& transform_operations =
+      static_cast<const WebTransformOperationsImpl&>(keyframe.value())
+          .AsTransformOperations();
+  curve_->AddKeyframe(cc::TransformKeyframe::Create(
+      base::TimeDelta::FromSecondsD(keyframe.time()), transform_operations,
+      cc::StepsTimingFunction::Create(steps, steps_start_offset)));
+}
+
 void WebTransformAnimationCurveImpl::setTimingFunction(
     TimingFunctionType type) {
   curve_->SetTimingFunction(CreateTimingFunction(type));
 }
 
 void WebTransformAnimationCurveImpl::setTimingFunction(double x1,
                                                        double y1,
                                                        double x2,
                                                        double y2) {
   curve_->SetTimingFunction(
       cc::CubicBezierTimingFunction::Create(x1, y1, x2, y2).Pass());
 }
 
 scoped_ptr<cc::AnimationCurve>
 WebTransformAnimationCurveImpl::CloneToAnimationCurve() const {
   return curve_->Clone();
 }
 
 }  // namespace cc_blink