Made GUI drag-n-drop work also in Firefox.

gui/index.html

@@ -45,8 +45,8 @@
 
 		<script>
 
-			var BlobBuilder = window.BlobBuilder || window.WebKitBlobBuilder || window.MozBlobBuilder;
-			var URL = window.URL || window.webkitURL || window.mozURL;
+			var BlobBuilderShim = window.BlobBuilder || window.WebKitBlobBuilder || window.MozBlobBuilder;
+			var URLShim = window.URL || window.webkitURL || window.mozURL;
 
 			var Signal = signals.Signal;
 
@@ -124,7 +124,7 @@
 				event.preventDefault();
 
 				var file = event.dataTransfer.files[ 0 ];
-				var extension = file.fileName.split( '.' )[1].toLowerCase();
+				var extension = file.name.split( '.' )[1].toLowerCase();
 				var reader = new FileReader();
 
 				reader.onload = function ( event ) {
@@ -151,10 +151,10 @@
 
 						case 'js':
 
-							var blob = new BlobBuilder();
+							var blob = new BlobBuilderShim();
 							blob.append( contents );
 
-							var url = window.URL.createObjectURL( blob.getBlob() );
+							var url = URLShim.createObjectURL( blob.getBlob() );
 
 							var loader = new THREE.JSONLoader();
 							loader.load( { model: url, callback: function ( geometry ) {