Optimize dartium dart:html bindings so real world application performance is acceptable. Improves d…

tools/dom/templates/html/impl/impl_HTMLDocument.darttemplate

Index: tools/dom/templates/html/impl/impl_HTMLDocument.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_HTMLDocument.darttemplate b/tools/dom/templates/html/impl/impl_HTMLDocument.darttemplate
index 61fc7150a0350e5b6e9b6180ac2e9fee432f6886..1a12fb8a49f7430ae03f5ca3e4448d1104306adc 100644
--- a/tools/dom/templates/html/impl/impl_HTMLDocument.darttemplate
+++ b/tools/dom/templates/html/impl/impl_HTMLDocument.darttemplate
@@ -413,7 +413,6 @@ $else
       }
       var elemProto = js.JsNative.callMethod(js.JsNative.getProperty(js.context, 'Object'), "create", [js.JsNative.getProperty(baseElement, 'prototype')]);
 
-      // Remember for any upgrading done in wrap_jso.
       addCustomElementType(tag, customElementClass, extendsTag);
 
       // TODO(terry): Hack to stop recursion re-creating custom element when the
@@ -430,13 +429,14 @@ $else
       int creating = 0;
 
       // If any JS code is hooked we want to call it too.
-      var oldCreatedCallback = elemProto['createdCallback'];
-      var oldAttributeChangedCallback = elemProto['attributeChangedCallback'];
-      var oldAttachedCallback = elemProto['attachedCallback'];
-      var oldDetachedCallback = elemProto['detachedCallback'];
-
-      // TODO(jacobr): warning:
-      elemProto['createdCallback'] = js.JsNative.withThis(($this) {
+      var oldCreatedCallback = js.JsNative.getProperty(elemProto, 'createdCallback');
+      var oldAttributeChangedCallback = js.JsNative.getProperty(elemProto, 'attributeChangedCallback');
+      var oldAttachedCallback = js.JsNative.getProperty(elemProto, 'attachedCallback');
+      var oldDetachedCallback = js.JsNative.getProperty(elemProto, 'detachedCallback');
+
+      // TODO(jacobr): this code seems far more complex than it should be
+      // unless I am missing something.
+      js.JsNative.setProperty(elemProto, 'createdCallback', js.allowInteropCaptureThis(($this) {
         if (_getJSClassName(reflectClass(customElementClass).superclass) != null && creating < 2) {
           creating++;
 
@@ -447,18 +447,17 @@ $else
               // Then upgrade that element to the customElementClass through
               // normal flow.
               dartClass = document.createElement(extendsTag);
-              js.setDartHtmlWrapperFor($this, dartClass);
-              dartClass.blink_jsObject = $this;
+              // TODO(jacobr): THIS MAKES NO SENSE. WAAT?
+
+              $this = js.JsNative.$setInstanceInterceptor($this, dartClass.runtimeType);
+              dartClass = $this; // THIS IS CRAZY CODE CODE BUT IT MATCHES WHAT HAD. WTH.. THIS CODE JUST SEEMS WRONG.
             }
 
             // Upgrade to the CustomElement Dart class.
             dartClass = _blink.Blink_Utils.constructElement(customElementClass, $this);
           } catch (e) {
             // Got a problem make it an HtmlElement and rethrow the error.
-            dartClass = HtmlElement.internalCreateHtmlElement();
-            // We need to remember the JS object (because constructElement failed
-            // it normally sets up the blink_jsObject.
-            dartClass.blink_jsObject = $this;
+            dartClass = js.JsNative.$setInstanceInterceptor($this, new HtmlElement.internalCreateHtmlElement().runtimeType);
 
             // Mark to only try this once don't try upgrading from HtmlElement
             // to the user's Dart class - we had a problem.
@@ -469,35 +468,36 @@ $else
             // return it and setup the blink_jsObject to the $this that we'll be working
             // with as we talk to blink.
             js.setDartHtmlWrapperFor($this, dartClass);
-
+            // TODO(jacobr) THIS MAKES NO SENSE BUT MATCHES WHAT WE HAD BEFORE.
+            js.JsNative.$setInstanceInterceptor($this, dartClass.runtimeType);
             creating--;
           }
         }
 
         if (oldCreatedCallback != null)
-          oldCreatedCallback.apply([], thisArg: unwrap_jso($this));
-      });
-      elemProto['attributeChangedCallback'] = new js.JsFunction.withThis(($this, attrName, oldVal, newVal) {
+          oldCreatedCallback.apply([], thisArg: $this);
+      }));
+      js.JsNative.setProperty(elemProto, 'attributeChangedCallback', js.allowInteropCaptureThis(($this, attrName, oldVal, newVal) {
         $this.attributeChanged(attrName, oldVal, newVal);
 
         if (oldAttributeChangedCallback != null)
-          oldAttributeChangedCallback.apply([], thisArg: unwrap_jso($this));
-      });
-      elemProto['attachedCallback'] = new js.JsFunction.withThis(($this) {
+          oldAttributeChangedCallback.apply([], thisArg: $this);
+      }));
+      js.JsNative.setProperty(elemProto, 'attachedCallback', js.allowInteropCaptureThis(($this) {
         $this.attached();
 
         if (oldAttachedCallback != null)
-          oldAttachedCallback.apply([], thisArg: unwrap_jso($this));
-      });
-      elemProto['detachedCallback'] = new js.JsFunction.withThis(($this) {
+          oldAttachedCallback.apply([], thisArg: $this);
+      }));
+      js.JsNative.setProperty(elemProto, 'detachedCallback', js.allowInteropCaptureThis(($this) {
         $this.detached();
 
         if (oldDetachedCallback != null)
-          oldDetachedCallback.apply([], thisArg: unwrap_jso($this));
-      });
+          oldDetachedCallback.apply([], thisArg: $this);
+      }));
       // document.registerElement('x-foo', {prototype: elemProto, extends: extendsTag});
       var jsMap = new js.JsObject.jsify({'prototype': elemProto, 'extends': extendsTag});
-      js.JsNative.callMethod(js.JsNative.getProperty(js.context, 'document'), 'registerElement', [tag, jsMap]);
+      js.JsNative.callMethod(document, 'registerElement', [tag, jsMap]);
     }
 $endif
   }