Restore multi-dialog restrictions for multi-world setups

history.txt

@@ -1667,3 +1667,5 @@ ______
 130425
 ------
 * Objects, Blocks, GUI, Store: Hide primitives feature
+* Morphic: Introducing World.stamp as reference in multi-World setups
+* Widgets: restore multi-dialog restrictions for multi-world setups

morphic.js

@@ -1035,7 +1035,7 @@
 /*global window, HTMLCanvasElement, getMinimumFontHeight, FileReader, Audio,
 FileList, getBlurredShadowSupport*/
 
-var morphicVersion = '2013-April-21';
+var morphicVersion = '2013-April-25';
 var modules = {}; // keep track of additional loaded modules
 var useBlurredShadows = getBlurredShadowSupport(); // check for Chrome-bug
 
@@ -9885,6 +9885,7 @@ WorldMorph.prototype.init = function (aCanvas, fillPage) {
     this.worldCanvas = aCanvas;
 
     // additional properties:
+    this.stamp = Date.now(); // reference in multi-world setups
     this.useFillPage = fillPage;
     if (this.useFillPage === undefined) {
         this.useFillPage = true;

widgets.js

@@ -2043,10 +2043,15 @@ DialogBoxMorph.prototype.withKey = function (key) {
 DialogBoxMorph.prototype.popUp = function (world) {
     if (world) {
         if (this.key) {
-            if (this.instances[this.key]) {
-                this.instances[this.key].destroy();
+            if (this.instances[world.stamp]) {
+                if (this.instances[world.stamp][this.key]) {
+                    this.instances[world.stamp][this.key].destroy();
+                }
+                this.instances[world.stamp][this.key] = this;
+            } else {
+                this.instances[world.stamp] = {};
+                this.instances[world.stamp][this.key] = this;
             }
-            this.instances[this.key] = this;
         }
         world.add(this);
         world.keyboardReceiver = this;