kactivities: C++11 feature test broken

[David Faure]

kactivities doesn't build for me with clang:

$ clang --version                                                      
clang version 3.5.0 (tags/RELEASE_350/final 216961)

cmake output :

-- Checking C++ support for auto
-- Checking C++ support for auto -- not supported
-- Checking C++ support for nullptr
-- Checking C++ support for nullptr -- works
-- Checking C++ support for lambda
-- Checking C++ support for lambda -- not supported
-- Checking C++ support for override
-- Checking C++ support for override -- works
-- Checking C++ support for unique_ptr
-- Checking C++ support for unique_ptr -- works
-- Checking C++ support for variadic-templates
-- Checking C++ support for variadic-templates -- works
-- Checking C++ support for initializer-lists
-- Checking C++ support for initializer-lists -- works
CMake Error at src/CMakeLists.txt:37 (message):
  You need a C++ compiler that supports the following C++11 features: auto,
  lambdas and move semantics.


-- Configuring incomplete, errors occurred!
See also "/s/kde/build/5/frameworks/kactivities/CMakeFiles/CMakeOutput.log".
Makefile:342: recipe for target 'cmake_check_build_system' failed
gmake: *** [cmake_check_build_system] Error 1

-- 
David Faure, faure at kde.org, http://www.davidfaure.fr
Working on KDE Frameworks 5
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