make helper to handle numeric timing input

Author: rjwright

src/group-constructors.js

@@ -22,13 +22,7 @@
     this._parent = null;
     this.children = children || [];
     this._reparent(this.children);
-    if (typeof timingInput == 'number') {
-      if (isNaN(timingInput)) {
-        timingInput = { duration: 0 };
-      } else {
-        timingInput = { duration: timingInput };
-      }
-    }
+    timingInput = shared.numericTimingToObject(timingInput);
     this._timingInput = shared.cloneTimingInput(timingInput);
     this._timing = shared.normalizeTimingInput(timingInput, true);
     this.timing = shared.makeTiming(timingInput, true, this);

src/keyframe-effect-constructor.js

@@ -56,13 +56,7 @@
   scope.KeyframeEffect = function(target, effectInput, timingInput) {
     this.target = target;
 
-    if (typeof timingInput == 'number') {
-      if (isNaN(timingInput)) {
-        timingInput = { duration: 0 };
-      } else {
-        timingInput = { duration: timingInput };
-      }
-    }
+    timingInput = shared.numericTimingToObject(timingInput);
     this._timingInput = shared.cloneTimingInput(timingInput);
     this._timing = shared.normalizeTimingInput(timingInput);
 

src/timing-utilities.js

@@ -137,14 +137,19 @@
     return timing;
   }
 
-  function normalizeTimingInput(timingInput, forGroup) {
+  function numericTimingToObject(timingInput) {
     if (typeof timingInput == 'number') {
       if (isNaN(timingInput)) {
         timingInput = { duration: 0 };
       } else {
         timingInput = { duration: timingInput };
       }
     }
+    return timingInput;
+  }
+
+  function normalizeTimingInput(timingInput, forGroup) {
+    timingInput = shared.numericTimingToObject(timingInput);
     var timing = makeTiming(timingInput, forGroup);
     timing._easing = toTimingFunction(timing.easing);
     return timing;
@@ -310,6 +315,7 @@
 
   shared.cloneTimingInput = cloneTimingInput;
   shared.makeTiming = makeTiming;
+  shared.numericTimingToObject = numericTimingToObject;
   shared.normalizeTimingInput = normalizeTimingInput;
   shared.calculateActiveDuration = calculateActiveDuration;
   shared.calculateTimeFraction = calculateTimeFraction;