clang/test/Index/code-completion-skip-bodies.cpp: Check stdout and stderr individually, rather than mixed output of stdout and stderr with 2>&1.

XFAIL(s) are removed.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@172705 91177308-0d34-0410-b5e6-96231b3b80d8