(early draft) Strict mode - throw exception on assignment to read only property.

src/handles.h

Index: src/handles.h
diff --git a/src/handles.h b/src/handles.h
index d95ca9117022d8d33c3bdfc5cc9dc32c8e7762e5..7e644b543bb8a75ec16d995ad319c7f8c21379b6 100644
--- a/src/handles.h
+++ b/src/handles.h
@@ -197,12 +197,14 @@ Handle<String> FlattenGetString(Handle<String> str);
 Handle<Object> SetProperty(Handle<JSObject> object,
                            Handle<String> key,
                            Handle<Object> value,
-                           PropertyAttributes attributes);
+                           PropertyAttributes attributes,
+                           StrictModeFlag strict);
 
 Handle<Object> SetProperty(Handle<Object> object,
                            Handle<Object> key,
                            Handle<Object> value,
-                           PropertyAttributes attributes);
+                           PropertyAttributes attributes,
+                           StrictModeFlag strict);
 
 Handle<Object> ForceSetProperty(Handle<JSObject> object,
                                 Handle<Object> key,
@@ -233,7 +235,8 @@ void SetLocalPropertyNoThrow(Handle<JSObject> object,
 Handle<Object> SetPropertyWithInterceptor(Handle<JSObject> object,
                                           Handle<String> key,
                                           Handle<Object> value,
-                                          PropertyAttributes attributes);
+                                          PropertyAttributes attributes,
+                                          StrictModeFlag strict);
 
 Handle<Object> SetElement(Handle<JSObject> object,
                           uint32_t index,