Dart2js option to dump info about compilation

sdk/lib/_internal/compiler/implementation/closure.dart

Index: sdk/lib/_internal/compiler/implementation/closure.dart
diff --git a/sdk/lib/_internal/compiler/implementation/closure.dart b/sdk/lib/_internal/compiler/implementation/closure.dart
index 2b0849402d20b22f767e7bcf383771021a762cb3..66325f75bc2d92161905314b36d29b8cb478a1b3 100644
--- a/sdk/lib/_internal/compiler/implementation/closure.dart
+++ b/sdk/lib/_internal/compiler/implementation/closure.dart
@@ -700,6 +700,8 @@ class ClosureTranslator extends Visitor {
         new FunctionElementX.from(Compiler.CALL_OPERATOR_NAME,
                                   element,
                                   globalizedElement);
+    ClosureContainer enclosing = element.enclosingElement;
+    enclosing.nestedClosures.add(callElement);
     globalizedElement.addMember(callElement, compiler);
     // The nested function's 'this' is the same as the one for the outer
     // function. It could be [null] if we are inside a static method.