Allow a closure to be torn off from itself via .call.

sdk/lib/_internal/lib/js_helper.dart

Index: sdk/lib/_internal/lib/js_helper.dart
diff --git a/sdk/lib/_internal/lib/js_helper.dart b/sdk/lib/_internal/lib/js_helper.dart
index 9147ae536e3aae27091536c0a31b24355b6255a4..4bd23f166cfa50cecf1cc27f7b6630233c5fdd40 100644
--- a/sdk/lib/_internal/lib/js_helper.dart
+++ b/sdk/lib/_internal/lib/js_helper.dart
@@ -2261,6 +2261,13 @@ abstract class Closure implements Function {
         '}');
   }
 
+  // Note that the backend adds the below special getter to allow for tearing
+  // off a closure from itself. We do this magically in the backend, as we do
+  // not want this getter to be visisble to resolution and the generation of

[karlklose, 2014/04/28 07:04:23]

'visisble' -> 'visible'.

Please add that we comment this method out on purpose (because we don't want it
to be visible).

Remove 'Note that'?

+  // extra stubs.
+  //
+  // Closure get call => this;
+
   String toString() => "Closure";
 }