Gracefully handle zero duration curves in CCActiveAnimation

cc/test/CCAnimationTestCommon.cpp

 // Copyright 2012 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 "config.h"
 
 #include "CCAnimationTestCommon.h"
 
 #include "CCKeyframedAnimationCurve.h"
 #include "CCLayerAnimationController.h"
@@ skipping 40 matching lines @@
     animation->setNeedsSynchronizedStartTime(true);
 
     target.addAnimation(animation.release());
 }
 
 } // namespace
 
 namespace WebKitTests {
 
 FakeFloatAnimationCurve::FakeFloatAnimationCurve()
+    : m_duration(1)
 {
 }
 
+FakeFloatAnimationCurve::FakeFloatAnimationCurve(double duration)
+    : m_duration(duration)
+{
+}
+
 FakeFloatAnimationCurve::~FakeFloatAnimationCurve()
 {
 }
 
 double FakeFloatAnimationCurve::duration() const
 {
-    return 1;
+    return m_duration;
 }
 
 float FakeFloatAnimationCurve::getValue(double now) const
 {
     return 0;
 }
 
 PassOwnPtr<cc::CCAnimationCurve> FakeFloatAnimationCurve::clone() const
 {
     return adoptPtr(new FakeFloatAnimationCurve);
@@ skipping 111 matching lines @@
 {
     addAnimatedTransform(layer, duration, deltaX, deltaY);
 }
 
 void addAnimatedTransformToLayer(cc::CCLayerImpl& layer, double duration, int deltaX, int deltaY)
 {
     addAnimatedTransform(*layer.layerAnimationController(), duration, deltaX, deltaY);
 }
 
 } // namespace WebKitTests