Revert "Revert "Dart2js support for custom element lifecycle events""

tools/dom/src/dart2js_CustomElementSupport.dart

Index: tools/dom/src/dart2js_CustomElementSupport.dart
diff --git a/tools/dom/src/dart2js_CustomElementSupport.dart b/tools/dom/src/dart2js_CustomElementSupport.dart
index 3ad3381896ddee83a3684d4686aca4a467d747a0..aa2c8f039af3153f2271d9c2139c50c96cb0507e 100644
--- a/tools/dom/src/dart2js_CustomElementSupport.dart
+++ b/tools/dom/src/dart2js_CustomElementSupport.dart
@@ -8,14 +8,22 @@ _callCreated(receiver) {
   return receiver.created();
 }
 
-_makeCreatedCallbackMethod() {
+_callEnteredView(receiver) {
+  return receiver.enteredView();
+}
+
+_callLeftView(receiver) {
+  return receiver.leftView();
+}
+
+_makeCallbackMethod(callback) {
   return JS('',
       '''((function(invokeCallback) {
              return function() {
                return invokeCallback(this);
              };
           })(#))''',
-      convertDartClosureToJS(_callCreated, 1));
+      convertDartClosureToJS(callback, 1));
 }
 
 const _typeNameToTag = const {
@@ -77,10 +85,18 @@ void _registerCustomElement(context, document, String tag, Type type,
 
   var properties = JS('=Object', '{}');
 
-  var jsCreatedCallback = _makeCreatedCallbackMethod();
-
   JS('void', '#.createdCallback = #', properties,
-      JS('=Object', '{value: #}', jsCreatedCallback));
+      JS('=Object', '{value: #}', _makeCallbackMethod(_callCreated)));
+  JS('void', '#.enteredViewCallback = #', properties,
+      JS('=Object', '{value: #}', _makeCallbackMethod(_callEnteredView)));
+  JS('void', '#.leftViewCallback = #', properties,
+      JS('=Object', '{value: #}', _makeCallbackMethod(_callLeftView)));
+
+  // TODO(blois): Bug 13220- remove once transition is complete
+  JS('void', '#.enteredDocumentCallback = #', properties,
+      JS('=Object', '{value: #}', _makeCallbackMethod(_callEnteredView)));
+  JS('void', '#.leftDocumentCallback = #', properties,
+      JS('=Object', '{value: #}', _makeCallbackMethod(_callLeftView)));
 
   var baseProto = JS('=Object', '#.prototype', baseConstructor);
   var proto = JS('=Object', 'Object.create(#, #)', baseProto, properties);