Make sure all new Code objects have a non-null PcDescriptors

runtime/vm/raw_object.h

 // 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.
 
 #ifndef VM_RAW_OBJECT_H_
 #define VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/globals.h"
 #include "vm/token.h"
@@ skipping 872 matching lines @@
 };
 
 
 class RawPcDescriptors : public RawObject {
   RAW_HEAP_OBJECT_IMPLEMENTATION(PcDescriptors);
 
   RawSmi* length_;  // Number of descriptors.
 
   // Variable length data follows here.
   intptr_t data_[0];
+
+  friend class Object;
 };
 
 
 // Stackmap is an immutable representation of the layout of the stack at a
 // PC. The stack map representation consists of a bit map which marks each
 // live object index starting from the base of the frame.
 //
 // The Stackmap also consists of a link to the code object corresponding to
 // the frame which the stack map is describing.  The bit map representation
 // is optimized for dense and small bit maps, without any upper bound.
@@ skipping 837 matching lines @@
   // Make sure this is updated when new TypedData types are added.
   ASSERT(kTypedDataInt8ArrayViewCid == kTypedDataInt8ArrayCid + 13);
   ASSERT(kExternalTypedDataInt8ArrayCid == kTypedDataInt8ArrayViewCid + 14);
   ASSERT(kNullCid == kExternalTypedDataInt8ArrayCid + 13);
   return (kNullCid - kTypedDataInt8ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_