Create a proxy that forwards to the default test allocator.
Declared in <bslma_stdtestallocator.h>
StdTestAllocator();
Create a proxy object which will forward allocation calls to the object pointed to by bslma::Default::defaultAllocator(). The default allocator must be a bslma::TestAllocator (or a type derived from it). Postcondition: ` this->mechanism() == bslma::Default::defaultAllocator(); `