[WIP] Fix element reordering without canvas

core/block_svg.js

@@ -292,7 +292,7 @@ Blockly.BlockSvg.prototype.setParent = function(newParent) {
     return;
   }
   var svgRoot = this.getSvgRoot();
-  if (this.parentBlock_ && svgRoot) {
+  if (this.parentBlock_ && svgRoot && this.workspace.getCanvas()) {
     // Move this block up the DOM.  Keep track of x/y translations.
     var xy = this.getRelativeToSurfaceXY();
     this.workspace.getCanvas().appendChild(svgRoot);

core/xml.js

@@ -417,12 +417,12 @@ Blockly.Xml.domToBlockHeadless_ = function(xmlBlock, workspace) {
         // Custom data for an advanced block.
         if (block.domToMutation) {
           block.domToMutation(xmlChild);
-	  /* disabling due to this being _headless_
+          /* disabling due to this being _headless_
           if (block.initSvg) {
             // Mutation may have added some elements that need initalizing.
             block.initSvg();
           }
-	  */
+          */
         }
         break;
       case 'comment':