Mark compiler-internal fields of closure objects as final.

runtime/vm/flow_graph_builder.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/flow_graph_builder.h"
 
 #include "lib/invocation_mirror.h"
 #include "vm/ast_printer.h"
 #include "vm/bit_vector.h"
 #include "vm/class_finalizer.h"
@@ skipping 2265 matching lines @@
                                                        cls,
                                                        arguments);
   alloc->set_closure_function(function);
 
   // Create fake fields for function and context. Only the context field is
   // stored at the allocation to be used later when inlining a closure call.
   const Field& function_field =
       Field::ZoneHandle(
           Field::New(Symbols::ClosureFunctionField(),
           false,  // !static
-          false,  // !final
+          true,  // final
           false,  // !const
           alloc->cls(),
           0));  // No token position.
   function_field.SetOffset(Closure::function_offset());
   const Field& context_field =
       Field::ZoneHandle(Field::New(
           Symbols::ClosureContextField(),
           false,  // !static
-          false,  // !final
+          true,  // final
           false,  // !const
           alloc->cls(),
           0));  // No token position.
   context_field.SetOffset(Closure::context_offset());
   alloc->set_context_field(context_field);
 
   Value* closure_val = Bind(alloc);
   { LocalVariable* closure_tmp_var = EnterTempLocalScope(closure_val);
     // Store function.
     Value* closure_tmp_val = Bind(new LoadLocalInstr(*closure_tmp_var));
@@ skipping 1619 matching lines @@
                                   LanguageError::kError,
                                   Heap::kNew,
                                   "FlowGraphBuilder Bailout: %s %s",
                                   String::Handle(function.name()).ToCString(),
                                   reason));
   Isolate::Current()->long_jump_base()->Jump(1, error);
 }
 
 
 }  // namespace dart