Revert "Do a second check for testing intrinsic types."

This reverts commit 4daa0b4c.

If the intrinsic has a slow-path, like charAt, the slow-path logic will complain as it only understands direct slow-paths, not virtual calls.

We should either override that decision in the slow-path, or replace the HInvokeVirtual when we're overriding the intrinsic choice.

Bug: 23475673
Change-Id: If55fbc8c82d52e0e7a7aec2674ae2bd2b74b5c77