Access to private members when constructing device vector from const view

[niermann999]

The member variables accessed in the constructor https://github.com/acts-project/vecmem/blob/521e240a55abe0385d256165581291af72875e9f/core/include/vecmem/containers/impl/device_vector.ipp#L36C25-L36C35 are private in the vector of different type device_vector<OTHERTYPE>, leading to errors such as:

traccc/build/_deps/vecmem-src/core/include/vecmem/containers/impl/device_vector.ipp:36:25: error: ‘vecmem::device_vector<const unsigned int>::size_type vecmem::device_vector<const unsigned int>::m_capacity’ is private within this context
   36 |     : m_capacity(parent.m_capacity),
```

[krasznaa]

You meant constructing a const_device vector from a non-const view... right? Since the other way is not meant to work.

[krasznaa]

Never mind, I see the issue...