Add min/max values for AudioParams

third_party/WebKit/LayoutTests/webaudio/resources/stereopanner-testing.js

 var StereoPannerTest = (function () {
 
   // Constants
   var PI_OVER_TWO = Math.PI * 0.5;
 
   var gSampleRate = 44100;
 
   // Time step when each panner node starts.
   var gTimeStep = 0.001;
 
@@ skipping 70 matching lines @@
     // to 0 to make the test fail to see what the actual error is.
     this.maxAllowedError = 1.3e-6;
 
     // Max (absolute) error and the index of the maxima for the left
     // and right channels.
     this.maxErrorL = 0;
     this.maxErrorR = 0;
     this.maxErrorIndexL = 0;
     this.maxErrorIndexR = 0;
 
+    // The maximum value to use for panner pan value. The value will range from -panLimit to
+    // +panLimit.
+    this.panLimit = 1.0625;
   }
 
 
   Test.prototype.init = function () {
     this.context = new OfflineAudioContext(2, gRenderLength, gSampleRate);
   };
 
   // Prepare an audio graph for testing. Create multiple impulse generators and
   // panner nodes, then play them sequentially while varying the pan position.
   Test.prototype.prepare = function () {
     var impulse;
     var impulseLength = Math.round(gTimeStep * gSampleRate);
     var sources = [];
     var panners = [];
 
     // Moves the pan value for each panner by pan step unit from -2 to 2.
     // This is to check if the internal panning value is clipped properly.
-    var panStep = 4 / (gNodesToCreate - 1);
+    var panStep = (2 * this.panLimit) / (gNodesToCreate - 1);
 
     if (this.numberOfInputChannels === 1) {
       impulse = createImpulseBuffer(this.context, impulseLength);
     } else {
       impulse = createStereoImpulseBuffer(this.context, impulseLength);
     }
 
     for (var i = 0; i < gNodesToCreate; i++) {
       sources[i] = this.context.createBufferSource();
       panners[i] = this.context.createStereoPanner();
       sources[i].connect(panners[i]);
       panners[i].connect(this.context.destination);
       sources[i].buffer = impulse;
-      panners[i].pan.value = this.panPositions[i] = panStep * i - 2;
+      panners[i].pan.value = this.panPositions[i] = panStep * i - this.panLimit;
 
       // Store the onset time position of impulse.
       this.onsets[i] = gTimeStep * i;
 
       sources[i].start(this.onsets[i]);
     }
   };
 
 
   Test.prototype.verify = function () {
@@ skipping 114 matching lines @@
 
 
   return {
     create: function (options) {
       return new Test(options);
     }
   };
 
 })();