Don't allow shadow blocks to be deleted.

core/block.js

@@ -463,7 +463,7 @@ Blockly.Block.prototype.getDescendants = function() {
  * @return {boolean} True if deletable.
  */
 Blockly.Block.prototype.isDeletable = function() {
-  return this.deletable_ &&
+  return this.deletable_ && !this.isShadow_ &&
       !(this.workspace && this.workspace.options.readOnly);
 };
 

core/xml.js

@@ -140,7 +140,7 @@ Blockly.Xml.blockToDom_ = function(block) {
   if (block.disabled) {
     element.setAttribute('disabled', true);
   }
-  if (!block.isDeletable()) {
+  if (!block.isDeletable() && !block.isShadow()) {
     element.setAttribute('deletable', false);
   }
   if (!block.isMovable() && !block.isShadow()) {

generators/dart/loops.js

@@ -146,7 +146,7 @@ Blockly.Dart['controls_forEach'] = function(block) {
       Blockly.Dart.ORDER_ASSIGNMENT) || '[]';
   var branch = Blockly.Dart.statementToCode(block, 'DO');
   branch = Blockly.Dart.addLoopTrap(branch, block.id);
-  var code = 'for (var ' + variable0 + ' in  ' + argument0 + ') {\n' +
+  var code = 'for (var ' + variable0 + ' in ' + argument0 + ') {\n' +
       branch + '}\n';
   return code;
 };