[c++-concepts] variable concept fixes

[Andrew Sutton]

> On 08/20/2014 08:56 PM, Andrew Sutton wrote:
>>
>> +  return VAR_P (decl)
>> +         && DECL_LANG_SPECIFIC (decl)
>> +         && DECL_DECLARED_CONCEPT_P (decl);
>
> this is brittle from the formatting point of view. Please double check in
> detail what I'm going to say, but I think that in such cases you simply want
> to wrap the whole thing in round parentheses.

Sorry, did you just mean to wrap the entire conjunction in parens? I'm
trying to find the formatting guidelines to check, but not succeeding
at the moment.

Andrew