Support use of external strings as inputs to LoadCodeUnitsInstr.

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/atomic.h"
 #include "vm/globals.h"
@@ skipping 1571 matching lines @@
     if (callback_ != NULL) (*callback_)(peer_);
   }
 
   const T* data() {
     return data_;
   }
   void* peer() {
     return peer_;
   }
 
+  static intptr_t data_offset() {
+    return OFFSET_OF(ExternalStringData<T>, data_);
+  }
+
  private:
   const T* data_;
   void* peer_;
   Dart_PeerFinalizer callback_;
 };
 
 
 class RawExternalOneByteString : public RawString {
   RAW_HEAP_OBJECT_IMPLEMENTATION(ExternalOneByteString);
+ public:
+  typedef ExternalStringData<uint8_t> ExternalData;
 
-  ExternalStringData<uint8_t>* external_data_;
+ private:
+  ExternalData* external_data_;
   friend class Api;
 };
 
 
 class RawExternalTwoByteString : public RawString {
   RAW_HEAP_OBJECT_IMPLEMENTATION(ExternalTwoByteString);
+ public:
+  typedef ExternalStringData<uint16_t> ExternalData;
 
-  ExternalStringData<uint16_t>* external_data_;
+ private:
+  ExternalData* external_data_;
   friend class Api;
 };
 
 
 class RawBool : public RawInstance {
   RAW_HEAP_OBJECT_IMPLEMENTATION(Bool);
 
   bool value_;
 };
 
@@ skipping 495 matching lines @@
   COMPILE_ASSERT(kExternalTypedDataInt8ArrayCid ==
                  kTypedDataInt8ArrayViewCid + 15);
   COMPILE_ASSERT(kByteBufferCid == kExternalTypedDataInt8ArrayCid + 14);
   COMPILE_ASSERT(kNullCid == kByteBufferCid + 1);
   return (kNullCid - kTypedDataInt8ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_