Consistent use of const for LookupResult.

src/property-details.h

Index: src/property-details.h
diff --git a/src/property-details.h b/src/property-details.h
index 5f0920b6705d5b19e39966bf2ed7c51af60cb089..7bc553a46be211749cf1f3cac6b4e4311d419b72 100644
--- a/src/property-details.h
+++ b/src/property-details.h
@@ -233,11 +233,11 @@ class PropertyDetails BASE_EMBEDDED {
         | FieldIndexField::encode(field_index);
   }
 
-  int pointer() { return DescriptorPointer::decode(value_); }
+  int pointer() const { return DescriptorPointer::decode(value_); }
 
   PropertyDetails set_pointer(int i) { return PropertyDetails(value_, i); }
 
-  PropertyDetails CopyWithRepresentation(Representation representation) {
+  PropertyDetails CopyWithRepresentation(Representation representation) const {
     return PropertyDetails(value_, representation);
   }
   PropertyDetails CopyAddAttributes(PropertyAttributes new_attributes) {
@@ -248,7 +248,7 @@ class PropertyDetails BASE_EMBEDDED {
 
   // Conversion for storing details as Object*.
   explicit inline PropertyDetails(Smi* smi);
-  inline Smi* AsSmi();
+  inline Smi* AsSmi() const;
 
   static uint8_t EncodeRepresentation(Representation representation) {
     return representation.kind();
@@ -258,26 +258,26 @@ class PropertyDetails BASE_EMBEDDED {
     return Representation::FromKind(static_cast<Representation::Kind>(bits));
   }
 
-  PropertyType type() { return TypeField::decode(value_); }
+  PropertyType type() const { return TypeField::decode(value_); }
 
   PropertyAttributes attributes() const {
     return AttributesField::decode(value_);
   }
 
-  int dictionary_index() {
+  int dictionary_index() const {
     return DictionaryStorageField::decode(value_);
   }
 
-  Representation representation() {
+  Representation representation() const {
     ASSERT(type() != NORMAL);
     return DecodeRepresentation(RepresentationField::decode(value_));
   }
 
-  int  field_index() {
+  int field_index() const {
     return FieldIndexField::decode(value_);
   }
 
-  inline PropertyDetails AsDeleted();
+  inline PropertyDetails AsDeleted() const;
 
   static bool IsValidIndex(int index) {
     return DictionaryStorageField::is_valid(index);