Web Animations API: Deferred computation of interpolated values

Source/core/animation/StringKeyframe.cpp

Index: Source/core/animation/StringKeyframe.cpp
diff --git a/Source/core/animation/StringKeyframe.cpp b/Source/core/animation/StringKeyframe.cpp
index c7124255aece91cecf5e98d473ec7efce8f881a9..1854d679a949da3d001f20ec0b150316bccb1ec3 100644
--- a/Source/core/animation/StringKeyframe.cpp
+++ b/Source/core/animation/StringKeyframe.cpp
@@ -6,6 +6,7 @@
 #include "core/animation/StringKeyframe.h"
 
 #include "core/animation/Interpolation.h"
+#include "core/animation/LegacyStyleInterpolation.h"
 #include "core/animation/css/CSSAnimations.h"
 #include "core/css/resolver/StyleResolver.h"
 #include "core/rendering/style/RenderStyle.h"
@@ -71,10 +72,14 @@ PassRefPtrWillBeRawPtr<Interpolation> StringKeyframe::PropertySpecificKeyframe::
         return DefaultStyleInterpolation::create(fromCSSValue, toCSSValue, property);
 
     switch (property) {
+    case CSSPropertyBorderBottomWidth:
+    case CSSPropertyBorderLeftWidth:
+    case CSSPropertyBorderRightWidth:
+    case CSSPropertyBorderTopWidth:

[alancutter (OOO until 2018), 2014/05/08 12:34:13]

The border width properties can change value according to the value of the
current border style.
It's simpler to use LengthStyleInterpolation to be responsive here than to
complicate the late binding detection with this quirk.

+    case CSSPropertyHeight:
     case CSSPropertyLeft:
     case CSSPropertyRight:
     case CSSPropertyWidth:
-    case CSSPropertyHeight:
         if (LengthStyleInterpolation::canCreateFrom(*fromCSSValue) && LengthStyleInterpolation::canCreateFrom(*toCSSValue))
             return LengthStyleInterpolation::create(fromCSSValue, toCSSValue, property);
         break;
@@ -84,13 +89,20 @@ PassRefPtrWillBeRawPtr<Interpolation> StringKeyframe::PropertySpecificKeyframe::
 
     // FIXME: Remove the use of AnimatableValues, RenderStyles and Elements here.
     // FIXME: Remove this cache
-    if (!m_animatableValueCache)
-        m_animatableValueCache = StyleResolver::createAnimatableValueSnapshot(*element, property, fromCSSValue);
+    if (!m_interpolableValuePromiseCache)
+        m_interpolableValuePromiseCache = InterpolableValuePromise::create(*element, property, fromCSSValue);
 
-    RefPtrWillBeRawPtr<AnimatableValue> to = StyleResolver::createAnimatableValueSnapshot(*element, property, toCSSValue);
-    toStringPropertySpecificKeyframe(end)->m_animatableValueCache = to;
+    RefPtrWillBeRawPtr<InterpolableValuePromise> to = InterpolableValuePromise::create(*element, property, toCSSValue);
+    toStringPropertySpecificKeyframe(end)->m_interpolableValuePromiseCache = to;
 
-    return LegacyStyleInterpolation::create(m_animatableValueCache.get(), to.release(), property);
+    return LegacyStyleInterpolation::create(m_interpolableValuePromiseCache, to.release(), property);
+}
+
+const PassRefPtrWillBeRawPtr<AnimatableValue> StringKeyframe::PropertySpecificKeyframe::getAnimatableValue() const
+{
+    if (m_interpolableValuePromiseCache)
+        return m_interpolableValuePromiseCache->extractAnimatableValue();
+    return nullptr;
 }
 
 PassOwnPtrWillBeRawPtr<Keyframe::PropertySpecificKeyframe> StringKeyframe::PropertySpecificKeyframe::neutralKeyframe(double offset, PassRefPtr<TimingFunction> easing) const
@@ -101,14 +113,14 @@ PassOwnPtrWillBeRawPtr<Keyframe::PropertySpecificKeyframe> StringKeyframe::Prope
 PassOwnPtrWillBeRawPtr<Keyframe::PropertySpecificKeyframe> StringKeyframe::PropertySpecificKeyframe::cloneWithOffset(double offset) const
 {
     Keyframe::PropertySpecificKeyframe* theClone = new PropertySpecificKeyframe(offset, m_easing, m_value.get());
-    toStringPropertySpecificKeyframe(theClone)->m_animatableValueCache = m_animatableValueCache;
+    toStringPropertySpecificKeyframe(theClone)->m_interpolableValuePromiseCache = m_interpolableValuePromiseCache;
     return adoptPtrWillBeNoop(theClone);
 }
 
 void StringKeyframe::PropertySpecificKeyframe::trace(Visitor* visitor)
 {
     visitor->trace(m_value);
-    visitor->trace(m_animatableValueCache);
+    visitor->trace(m_interpolableValuePromiseCache);
     Keyframe::PropertySpecificKeyframe::trace(visitor);
 }