Mock up all remaining core library implementation classes.

dart/frog/leg/ssa/builder.dart

Index: dart/frog/leg/ssa/builder.dart
diff --git a/dart/frog/leg/ssa/builder.dart b/dart/frog/leg/ssa/builder.dart
index 192ead9bcd266177386e888ee165ae53c73ad0a3..39fb7b83163839b35165fe816b6aae307ed96599 100644
--- a/dart/frog/leg/ssa/builder.dart
+++ b/dart/frog/leg/ssa/builder.dart
@@ -320,7 +320,7 @@ class LocalsHandler {
     if (isAccessedDirectly(element)) {
       if (directLocals[element] == null) {
         builder.compiler.internalError(
-            "Could not find value", node: element.parseNode(builder.compiler));
+            "Could not find value", element: element);

[ngeoffray, 2012/02/17 10:03:50]

This is exactly what we talked about with Florian: not cancel on elements in the
backend. I believe it's on his TODO list to clean up error reporting in the
backend.

[floitsch, 2012/02/17 10:40:40]

While you are it: with "Cannot find value" it fits on one line (I think).

[ahe, 2012/02/17 16:26:46]

Done.

       }
       return directLocals[element];
     } else if (isStoredInClosureField(element)) {