Introduce FieldIndex to unify and abstract property/field offset

src/objects-printer.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/disassembler.h"
 #include "src/disasm.h"
 #include "src/jsregexp.h"
 #include "src/objects-visiting.h"
@@ skipping 214 matching lines @@
 
 void JSObject::PrintProperties(FILE* out) {
   if (HasFastProperties()) {
     DescriptorArray* descs = map()->instance_descriptors();
     for (int i = 0; i < map()->NumberOfOwnDescriptors(); i++) {
       PrintF(out, "   ");
       descs->GetKey(i)->NamePrint(out);
       PrintF(out, ": ");
       switch (descs->GetType(i)) {
         case FIELD: {
-          int index = descs->GetFieldIndex(i);
+          FieldIndex index = FieldIndex::ForDescriptor(map(), i);
           RawFastPropertyAt(index)->ShortPrint(out);
-          PrintF(out, " (field at offset %d)\n", index);
+          PrintF(out, " (field at offset %d)\n", index.property_index());
           break;
         }
         case CONSTANT:
           descs->GetConstant(i)->ShortPrint(out);
           PrintF(out, " (constant)\n");
           break;
         case CALLBACKS:
           descs->GetCallbacksObject(i)->ShortPrint(out);
           PrintF(out, " (callback)\n");
           break;
@@ skipping 1009 matching lines @@
     }
   }
   PrintF(out, "\n");
 }
 
 
 #endif  // OBJECT_PRINT
 
 
 } }  // namespace v8::internal