Attempting to appease the build bots on systems with ansi escape sequences.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@198887 91177308-0d34-0410-b5e6-96231b3b80d8
Have attribute 'objc_precise_lifetime' suppress -Wunused.

Fixes <rdar://problem/15596883>

In ARC, __attribute__((objc_precise_lifetime)) guarantees that the
object stored in it will survive to the end of the variable's formal
lifetime.  It is therefore useful even if it completely unused.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@198888 91177308-0d34-0410-b5e6-96231b3b80d8
Preserve -fretain-comments-from-system-headers in modules

Preserves the setting of -fretain-comments-from-system-headers when
building/saving/loading module files. This allows code completion to pick up
documentation comments from system modules.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@198890 91177308-0d34-0410-b5e6-96231b3b80d8