r180591 - Add r180263 back, but fix hasBraces() to be correct during parsing.

[Rafael Espíndola]

>>>   /// Language - The language for this linkage specification.
>>>   LanguageIDs Language;
>>> +  /// True if this linkage spec has brances. This is needed so that hasBraces()
>>> +  /// returns the correct result while the linkage spec body is being parsed.
>>> +  /// Once RBraceLoc has been set this is not used, so it doesn't need to be
>>> +  /// serialized.
>>> +  bool HasBraces;
>
> Please turn this and the Language member into bit fields to shrink the size of this class.

r180601.

Thanks,
Rafael