Plumb timeToNextEffect through players and animation

Source/core/animation/TimedItem.h

Index: Source/core/animation/TimedItem.h
diff --git a/Source/core/animation/TimedItem.h b/Source/core/animation/TimedItem.h
index 31520fc4ebefe349a3227de35550923c523c0a43..285d8df78c8cc03f3e14fe339239ed6bebf5f86f 100644
--- a/Source/core/animation/TimedItem.h
+++ b/Source/core/animation/TimedItem.h
@@ -74,6 +74,7 @@ public:
     bool isCurrent() const { return ensureCalculated().isCurrent; }
     bool isInEffect() const { return ensureCalculated().isInEffect; }
     bool isInPlay() const { return ensureCalculated().isInPlay; }
+    double timeToEffectChange() const { return ensureCalculated().timeToEffectChange; }
 
     double startTime() const { return m_startTime; }
 
@@ -94,6 +95,7 @@ protected:
     virtual void updateChildrenAndEffects(bool wasInEffect) const = 0;
     virtual double intrinsicIterationDuration() const { return 0; };
     virtual void willDetach() = 0;
+    virtual double calculateTimeToEffectChange(double inheritedTime, double activeTime, Phase) const = 0;

[Timothy Loh, 2013/10/18 06:01:27]

Can we make this private? I think protected-virtual is for virtual functions
where you want to be able to explicitly call your ancestors' functions, while
private-virtual disallows this.

[shans, 2013/10/21 00:37:57]

private-virtual disallows *any* access to the ancestor version of the function,
so it's impossible to e.g. define a single version at the top of an inheritance
subtree - every class needs to have its own implementation (or be abstract).

calculateTimeToEffectChange can probably be made private for now
(updateChildrenAndEffects and willDetach too), but we'll likely run into this
issue at some point in the future. In constract, we already can't make
intrinsicIterationDuration private because we have a default implementation in
TimedItem.

I think I'd rather keep all of these functions at the same level of access
(they're all part of the same process and will evolve together as we support the
rest of the model), but I don't feel particularly strongly about it.

 
 private:
     void attach(Player* player) { m_player = player; };
@@ -120,6 +122,7 @@ private:
         bool isCurrent;
         bool isInEffect;
         bool isInPlay;
+        double timeToEffectChange;
     } m_calculated;
     mutable bool m_isFirstSample;