Const qualify __mem_fn call operator

QOI improvement.

Differential Revision: http://llvm-reviews.chandlerc.com/D2059

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@199848 91177308-0d34-0410-b5e6-96231b3b80d8
Rename some internal templates to avoid conflict with complier intrinsics. __is_constructible --> __libcpp_is_constructible, __is_nothrow_constructible --> __libcpp_is_nothrow_constructible, and __is_nothrow_assignable --> __libcpp_is_nothrow_assignable. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@200010 91177308-0d34-0410-b5e6-96231b3b80d8
Removed extra line that I left in when committing 199694. Thanks to Jared Grubb for the catch.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@200108 91177308-0d34-0410-b5e6-96231b3b80d8
don't bother testing which clang++ if cxx_under_test is set
Merge branch 'master' into powerpc-darwin8
stray semicolons polluting compile command by cmake, kill with fire
lit.site.cfg:cxx_under_test should take precedence over 'which clang++'
(reviewed by Marshall Clow)

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@200364 91177308-0d34-0410-b5e6-96231b3b80d8
Merge branch 'master' into powerpc-darwin8
protect undefined macros from being evaluated (darwin10), fixes [bug 18664]