[printing] Print properties backing store value and add a gdb macro for printing LayoutDescriptors.

src/layout-descriptor.h

 // Copyright 2014 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.
 
 #ifndef V8_LAYOUT_DESCRIPTOR_H_
 #define V8_LAYOUT_DESCRIPTOR_H_
 
 #include <iosfwd>
 
 #include "src/objects.h"
@@ skipping 65 matching lines @@
   // only when corresponding descriptors array is trimmed.
   // The layout descriptor could be trimmed if it was slow or it could
   // become fast.
   LayoutDescriptor* Trim(Heap* heap, Map* map, DescriptorArray* descriptors,
                          int num_descriptors);
 
 #ifdef OBJECT_PRINT
   // For our gdb macros, we should perhaps change these in the future.
   void Print();
 
+  void ShortPrint(std::ostream& os);
   void Print(std::ostream& os);  // NOLINT
 #endif
 
   // Capacity of layout descriptors in bits.
   V8_INLINE int capacity();
 
   static Handle<LayoutDescriptor> NewForTesting(Isolate* isolate, int length);
   LayoutDescriptor* SetTaggedForTesting(int field_index, bool tagged);
 
  private:
@@ skipping 54 matching lines @@
 
  private:
   bool all_fields_tagged_;
   int header_size_;
   LayoutDescriptor* layout_descriptor_;
 };
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_LAYOUT_DESCRIPTOR_H_