Fix some issues with RefBase debugging.

First slipt sp<> out of RefBase into StrongPointer.h so it can be reused
more easily and to make it clear that it doesn't require RefBase.

Note: the rest of the change only affects the system when DEBUG_REFS is enabled.

The main problem we fix here is that the owner id associated with each
reference could get out of date when a sp<> or wp<> was moved, for
instance when they're used in a Vector< >.

We fix this issue by calling into RefBase::moveReferences from
a template specialization for sp<TYPE> and wp<TYPE> of the
type helpers. RefBase::moveReferences() has then a chance to
update the owner ids.

There is a little bit of trickery to implement this generically in
RefBase, where we need to use a templatized functor that can turn
a sp<TYPE>* casted to a void* into a RefBase*.

Introduced a new debug option DEBUG_REFS_FATAL_SANITY_CHECKS
currently set to 0 by default as there seem to be an issue
with sp<ANativeWindow> which trips the sanity checks.

Change-Id: I4825b21c8ec47d4a0ef35d760760ae0c9cdfbd7f