Start new design for interceptors and implement String.charCodeAt with it.

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

Index: sdk/lib/_internal/compiler/implementation/compiler.dart
===================================================================
--- sdk/lib/_internal/compiler/implementation/compiler.dart	(revision 14732)
+++ sdk/lib/_internal/compiler/implementation/compiler.dart	(working copy)
@@ -135,6 +135,14 @@
   Element functionApplyMethod;
   Element invokeOnMethod;
 
+  ClassElement jsStringClass;

[ahe, 2012/11/09 13:45:29]

Backend specific?

[ngeoffray, 2012/11/13 11:45:16]

Done.

+  ClassElement objectInterceptorClass;

[ahe, 2012/11/09 13:45:29]

Ditto.

[ngeoffray, 2012/11/13 11:45:16]

Done.

+  Element getInterceptorMethod;

[ahe, 2012/11/09 13:45:29]

Ditto.

[ngeoffray, 2012/11/13 11:45:16]

Done.

+
+  bool isForeignClass(Element element) {

[ahe, 2012/11/09 13:45:29]

Ditto.

[ngeoffray, 2012/11/13 11:45:16]

Done.

+    return element == jsStringClass;
+  }
+
   Element get currentElement => _currentElement;
   withCurrentElement(Element element, f()) {
     Element old = currentElement;
@@ -443,6 +451,12 @@
     jsInvocationMirrorClass.ensureResolved(this);
     invokeOnMethod = jsInvocationMirrorClass.lookupLocalMember(
         const SourceString('invokeOn'));
+
+    jsStringClass = interceptorsLibrary.find(const SourceString('JSString'));
+    objectInterceptorClass =
+        interceptorsLibrary.find(const SourceString('ObjectInterceptor'));
+    getInterceptorMethod =
+        interceptorsLibrary.find(const SourceString('getInterceptor'));
   }
 
   void loadCoreImplLibrary() {