Revert commit r219297.
Still troubles with OpenMP/parallel_firstprivate_codegen.cpp (now in ARM buildbots).


git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@219298 91177308-0d34-0410-b5e6-96231b3b80d8
Remove threshold on object size for inserting lifetime begin / end

Boostrapping LLVM+Clang+LLDB without threshold on object size for
lifetime markers insertion has shown there was no significant change
in compile time, so let the stack slot colorizer do its optimization
for all slots.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@219303 91177308-0d34-0410-b5e6-96231b3b80d8