Pass explicit C++ version to test
Pass explicit C++ version to test

stop-hook-threads.cpp uses C++11 features, so ask for C++11 explicitely.
This isn't broken on mainstream because clang defaults to a newer C++
version now, but it breaks if testing against an older compiler.

git-svn-id: 4c4cc70b1ef44ba2b7963015e681894188cea27e@359349 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb