Replace ToAsciiVector and ToUC16Vector with single function that returns a tagged value.

src/objects-inl.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 279 matching lines @@
   return (type_ & kStringRepresentationMask) == kSeqStringTag;
 }
 
 
 StringRepresentationTag StringShape::representation_tag() {
   uint32_t tag = (type_ & kStringRepresentationMask);
   return static_cast<StringRepresentationTag>(tag);
 }
 
 
+uint32_t StringShape::encoding_tag() {
+  return type_ & kStringEncodingMask;
+}
+
+
 uint32_t StringShape::full_representation_tag() {
   return (type_ & (kStringRepresentationMask | kStringEncodingMask));
 }
 
 
 STATIC_CHECK((kStringRepresentationMask | kStringEncodingMask) ==
              Internals::kFullStringRepresentationMask);
 
 
 bool StringShape::IsSequentialAscii() {
@@ skipping 4298 matching lines @@
 #undef WRITE_INT_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_