PR 44436 Associative containers emplace/emplace_hint

[François Dumont]

> Typo: emplate.
>> Ok to commit ?
> I say let's just wait another couple of days for more comments and 
> then let's go ahead. Patch looks fine to me (thanks again!) and we 
> want the code to be available if we want to catch subtler issue in 
> time for the release of 4.8.0. Personally, I'm mostly a bit nervous 
> about the various const-ness changes, but we should be Ok in terms of 
> testing, because in C++11 the various insert and emplace take 
> const_iterators. I'm thinking: remember to run the performance 
> testsuite, it should provide quite a bit of additional testing of the 
> old insert calls.
>
> Oh well, if you are willing to mechanically add the new functions to 
> the profile-mode code too, it would be great. Otherwise I can 
> certainly do it.
>
> Thanks,
> Paolo.
>

     I don't worry with the constness modifications, I simply realized 
that those methods where always invoked with _Base_ptr and not 
_Const_Base_ptr. As it allows to remove a const_cast in _M_insert_ I 
prefer to simplify the code.

     I will run performance tests and the check the profile mode. It 
should be ready when we decide to apply the patch.

François