In an effort to disentangle the three sets of llvm headers the targets
in stlib uses (real llvm headers, RuntimeHeaders/llvm,
stdlib/include/llvm), this patch completely removes the includes from
the runtime to RemoteInspection.
This is the first patch to eventually completely remove
RuntimeHeaders/llvm headers.
The `-Winvalid-offsetof` warning is valid in this case. `offsetof` is
being applied to types with a non-standard layout. The layout of this
type is undefined by the specification. There is no guarantee that the
type layout is uniform across all ABIs. It is not possible to portably
compute the offset statically, especially efficiently.
Sink this check into a unit test to avoid performing this test at
runtime. In order to do this in the standard library, we would need to
do this check through a global constructor.