Revert "[ASan/Win] Remove a hack that seems not to be required with VS2013 anymore" (r215708)

This is still needed for VS2012.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@215930 91177308-0d34-0410-b5e6-96231b3b80d8
sanitizer_printf.cc: guard the va_copy hack on _MSC_VER

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@215932 91177308-0d34-0410-b5e6-96231b3b80d8
profile: Improve error messages on bad GCDA files

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@215933 91177308-0d34-0410-b5e6-96231b3b80d8