VM: Add infrastructure to support deferred generation of unoptimized code.

runtime/vm/intermediate_language.h

 // Copyright (c) 2013, 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.
 
 #ifndef VM_INTERMEDIATE_LANGUAGE_H_
 #define VM_INTERMEDIATE_LANGUAGE_H_
 
 #include "vm/allocation.h"
 #include "vm/ast.h"
 #include "vm/growable_array.h"
@@ skipping 7997 matching lines @@
   Environment(intptr_t length,
               intptr_t fixed_parameter_count,
               intptr_t deopt_id,
               const ParsedFunction& parsed_function,
               Environment* outer)
       : values_(length),
         locations_(NULL),
         fixed_parameter_count_(fixed_parameter_count),
         deopt_id_(deopt_id),
         parsed_function_(parsed_function),
-        outer_(outer) { }
+        outer_(outer) {
+    ASSERT(!parsed_function_.code().IsNull());
+  }
 
 
   GrowableArray<Value*> values_;
   Location* locations_;
   const intptr_t fixed_parameter_count_;
   intptr_t deopt_id_;
   const ParsedFunction& parsed_function_;
   Environment* outer_;
 
   DISALLOW_COPY_AND_ASSIGN(Environment);
@@ skipping 39 matching lines @@
   LocationSummary* Name::MakeLocationSummary(Zone* zone, bool opt) const {    \
     UNIMPLEMENTED();                                                          \
     return NULL;                                                              \
   }                                                                           \
   void Name::EmitNativeCode(FlowGraphCompiler* compiler) { UNIMPLEMENTED(); }
 
 
 }  // namespace dart
 
 #endif  // VM_INTERMEDIATE_LANGUAGE_H_