Fixing API; addressing @mpriour's doc comment

Previously, minFrameRate could not be set as option with the start method.
The tests failed to catch this flaw. Now both the start method and the
tests are fixed.

lib/OpenLayers/Tween.js

@@ -54,12 +54,12 @@ OpenLayers.Tween = OpenLayers.Class({
     
     /**
      * APIProperty: minFrameRate
-     * {Number} The minimum framerate for animations. After each step, the time
+     * {Number} The minimum framerate for animations in frames per second. After
-     * spent in the animation is compared to the calculated time at this frame
+     * each step, the time spent in the animation is compared to the calculated
-     * rate. If the animation runs longer than the calculated time, the next
+     * time at this frame rate. If the animation runs longer than the calculated
-     * step is skipped.
+     * time, the next step is skipped. Default is 30.
      */
-    minFrameRate: 30,
+    minFrameRate: null,
 
     /**
      * Property: startTime
@@ -99,7 +99,8 @@ OpenLayers.Tween = OpenLayers.Class({
      * begin - {Object} values to start the animation with
      * finish - {Object} values to finish the animation with
      * duration - {int} duration of the tween (number of steps)
-     * options - {Object} hash of options (for example callbacks (start, eachStep, done))
+     * options - {Object} hash of options (callbacks (start, eachStep, done),
+     *     minFrameRate)
      */
     start: function(begin, finish, duration, options) {
         this.playing = true;
@@ -107,6 +108,7 @@ OpenLayers.Tween = OpenLayers.Class({
         this.finish = finish;
         this.duration = duration;
         this.callbacks = options.callbacks;
+        this.minFrameRate = options.minFrameRate || 30;
         this.time = 0;
         this.startTime = new Date().getTime();
         OpenLayers.Animation.stop(this.animationId);

tests/Tween.html

@@ -79,29 +79,32 @@
         t.plan(2);
         
         var tween = new OpenLayers.Tween();
-        var log1 = 0;
+        var log = 0;
         tween.start({count: 0}, {count: 10}, 10, {
             callbacks: {
                 eachStep: function() {
-                    log1++;
+                    log++;
                 }
             },
             minFrameRate: 10000
         });
         
-        var log2 = 0;
-        tween.start({count: 0}, {count: 10}, 10, {
-            callbacks: {
-                eachStep: function() {
-                    log2++;
-                }
-            },
-            minFrameRate: 1
-        });
-
         t.delay_call(0.8, function() {
-            t.eq(log1, 0, 'all frames skipped at a frame rate of 10000');            
+            t.eq(log, 0, 'all frames skipped at a frame rate of 10000');
-            t.eq(log2, 11, 'no frames skipped at a frame rate of 1');            
+            
+            log = 0;
+            tween.start({count: 0}, {count: 10}, 10, {
+                callbacks: {
+                    eachStep: function() {
+                        log++;
+                    }
+                },
+                minFrameRate: 1
+            });
+        });
+        
+        t.delay_call(1.6, function() {
+            t.eq(log, 11, 'no frames skipped at a frame rate of 1');            
         });
     }