Identify the name of the prototype extended by out-of-app custom elements

pkg/web_components/lib/dart_support.js

Index: pkg/web_components/lib/dart_support.js
diff --git a/pkg/web_components/lib/dart_support.js b/pkg/web_components/lib/dart_support.js
index 4e1995a4e2840564771c22dee5d0c37f25019821..7d73f50979b616658d5ad7da32e33c1082db8e34 100644
--- a/pkg/web_components/lib/dart_support.js
+++ b/pkg/web_components/lib/dart_support.js
@@ -116,6 +116,28 @@
     upgraders[name] = upgrader;
   }
 
+  // dartNativeDispatchHooksTransformer is described on initHooks() in
+  // sdk/lib/_internal/lib/native_helper.dart.
+  if (typeof window.dartNativeDispatchHooksTransformer == 'undefined')
+    window.dartNativeDispatchHooksTransformer = [];
+
+  window.dartNativeDispatchHooksTransformer.push(function(hooks) {

[Siggi Cherem (dart-lang), 2014/06/11 19:34:57]

should we also check for !!ShadowDOMPOlyfill?

Seems that we don't need to use this hook if we already have the other hook
above.

[sra1, 2014/06/11 19:43:24]

Done.

+    var originalGetUnknownTag = hooks.getUnknownTag;
+    hooks.getUnknownTag = function(o, tag) {
+      // Custom elements outside the app in chrome have a constructor
+      // names like "x-b".

[Siggi Cherem (dart-lang), 2014/06/11 19:34:57]

nit: say x-tag instead of x-b (more commonly used for comments :-))

[sra1, 2014/06/11 19:43:24]

Done.

+      if (/-/.test(tag)) {
+        var s = Object.prototype.toString.call(o);
+	var match = s.match(/^\[object ([A-Za-z]*)\]$/);

[Siggi Cherem (dart-lang), 2014/06/11 19:34:57]

let's add Element in the regex

[sra1, 2014/06/11 19:43:24]

Done.

+        if (match) {
+          var name = match[1];
+          if (name != "Object") return name;
+	}
+        return originalGetUnknownTag(o, tag);
+      }
+    };
+  });
+
   doc._registerDartTypeUpgrader = registerDartTypeUpgrader;
   doc.registerElement = registerElement;
 })(document);