Bug 1198708 - Part 5: Add method to serialize a ComputedTimingFunction. r=birtles

dom/animation/KeyframeEffect.cpp

@@ -10,6 +10,7 @@
 #include "AnimationCommon.h"
 #include "nsCSSPropertySet.h"
 #include "nsCSSProps.h" // For nsCSSProps::PropHasFlags
+#include "nsStyleUtil.h"
 
 namespace mozilla {
 
@@ -53,6 +54,28 @@ ComputedTimingFunction::GetValue(double aPortion) const
   return StepEnd(mSteps, aPortion);
 }
 
+void
+ComputedTimingFunction::AppendToString(nsAString& aResult) const
+{
+  switch (mType) {
+    case nsTimingFunction::Type::CubicBezier:
+      nsStyleUtil::AppendCubicBezierTimingFunction(mTimingFunction.X1(),
+                                                   mTimingFunction.Y1(),
+                                                   mTimingFunction.X2(),
+                                                   mTimingFunction.Y2(),
+                                                   aResult);
+      break;
+    case nsTimingFunction::Type::StepStart:
+    case nsTimingFunction::Type::StepEnd:
+      nsStyleUtil::AppendStepsTimingFunction(mType, mSteps, mStepSyntax,
+                                             aResult);
+      break;
+    default:
+      nsStyleUtil::AppendCubicBezierKeywordTimingFunction(mType, aResult);
+      break;
+  }
+}
+
 // In the Web Animations model, the iteration progress can be outside the range
 // [0.0, 1.0] but it shouldn't be Infinity.
 const double ComputedTiming::kNullProgress = PositiveInfinity<double>();

dom/animation/KeyframeEffect.h

@@ -130,6 +130,7 @@ public:
   bool operator!=(const ComputedTimingFunction& aOther) const {
     return !(*this == aOther);
   }
+  void AppendToString(nsAString& aResult) const;
 
 private:
   Type mType;