Contradiction in C++ style guide about scoped_ptr

```
The C++ style guide gives two contradicting guidelines about using scoped_ptr.
The Ownership and Smart Pointers section explicitly says not to use scoped_ptr
except for backward compatibility, while the section on Variable-Length Arrays
and alloca() lists scoped_ptr as an acceptable alternative.
```

Original issue reported on code.google.com by `jcrot...@gmail.com` on 2 May 2014 at 2:38