Change the default panning mode from HRTF to equal-power

LayoutTests/webaudio/resources/panner-model-testing.js

Index: LayoutTests/webaudio/resources/panner-model-testing.js
diff --git a/LayoutTests/webaudio/resources/panner-model-testing.js b/LayoutTests/webaudio/resources/panner-model-testing.js
index f96857f8dd181410f17b33026eee231fee027133..6c853877b256b098dcc31e8c84028f88a6c6a60f 100644
--- a/LayoutTests/webaudio/resources/panner-model-testing.js
+++ b/LayoutTests/webaudio/resources/panner-model-testing.js
@@ -21,7 +21,7 @@ var bufferSource;
 var panner;
 var position;
 var time;
-      
+
 var renderedBuffer;
 var renderedLeft;
 var renderedRight;
@@ -46,6 +46,8 @@ function createGraph(context, nodeCount) {
         bufferSource[k].buffer = impulse;
 
         panner[k] = context.createPanner();
+        // Equalpower is default now. May not be necessary.
+        // https://code.google.com/p/chromium/issues/detail?id=424356
         panner[k].panningModel = "equalpower";

[Raymond Toy, 2014/10/17 17:39:30]

I would just remove the comment and the assignment.  If somebody in the future
changes the default panning model, this will be caught here and in the other
layout test where you check that the default model is "equalpower"

[hongchan, 2014/10/17 18:13:41]

Done.

         panner[k].distanceModel = "linear";
 
@@ -92,17 +94,17 @@ function equalPowerGain(angle) {
     } else {
         if (azimuth <= 0) {
             var panPosition = (azimuth + 90) / 90;
-    
+

[Raymond Toy, 2014/10/17 17:39:30]

Removing more blank lines?

[hongchan, 2014/10/17 18:13:41]

Yes.

             var gainL = 1 + Math.cos(0.5 * Math.PI * panPosition);
             var gainR = Math.sin(0.5 * Math.PI * panPosition);
-    
+
             return { left : gainL, right : gainR };
         } else {
             var panPosition = azimuth / 90;
-    
+
             var gainL = Math.cos(0.5 * Math.PI * panPosition);
             var gainR = 1 + Math.sin(0.5 * Math.PI * panPosition);
-    
+
             return { left : gainL, right : gainR };
         }
     }
@@ -117,7 +119,7 @@ function checkResult(event) {
     // expected value.  This value is experimentally determined.  Set
     // to 0 to make the test fail to see what the actual error is.
     var maxAllowedError = 1.3e-6;
-  
+
     var success = true;
 
     // Number of impulses found in the rendered result.
@@ -191,7 +193,7 @@ function checkResult(event) {
         testFailed("Left channel gain values are incorrect.  Max error = " + maxErrorL + " at time " + time[maxErrorIndexL] + " (threshold = " + maxAllowedError + ")");
         success = false;
     }
-    
+
     if (maxErrorR <= maxAllowedError) {
         testPassed("Right channel gain values are correct.");
     } else {