Loader: Remove support for DbgColor. See #7368.

src/loaders/Loader.js

@@ -126,12 +126,9 @@ THREE.Loader.prototype = {
 
 				switch ( name ) {
 					case 'DbgColor':
-						if ( json.color === undefined ) json.color = value;
-						break;
 					case 'DbgIndex':
 					case 'opticalDensity':
 					case 'illumination':
-						// These were never supported
 						break;
 					case 'DbgName':
 						json.name = value;