This commit updates unit test modules to be defined under the `ot`
namespace. This aligns all the unit tests to follow the same
model, eliminating the need to use `ot::` prefix in unit test
code.
This commit moves the `instance` module to a newly added folder
`core/instance` (from `core/common`. Header file `extension.hpp`
and its example is also moved to the same folder.
This commit updates `VerifyOrQuit()` and `SuccessOrQuit()` macros to
include the failed condition in the error message that is printed on
a failure (in addition to function name and line number where the
error happened). This commit also changes the second parameter
(`aMessage`) to in these macros to be optional.
This commit also updates unit tests to remove the second `aMessage`
string in cases where the failure can be inferred from the condition
itself.
This commit adds a template `Pool<Type, kPoolSize>` class representing
an object pool. `Message`, `Netif`, and `AddressResolver` classes are
respectively updated to use `Pool` for managing their buffer pool,
external unicast/multicast address pool, and address cache entry pool.
This commit also adds a unit test for the `Pool` class.
Abtin Keshavarzian