Revert "compiler/natives/src/reflect: Don't skip string internalization for types."
Revert "compiler/natives/src/reflect: Don't skip string internalization for types."

This reverts commit 2f2d5b34a708e719976d9e5bf6184bdba80ec4fb.

That commit (and its commit message) was wrong/incomplete. Now I
understand there was a reason for skipping string internalization
for types. The following commit is a better alternative fix.

gopherjs/gopherjs,gopherjs/gopherjs,gopherjs/gopherjs,gopherjs/gopherjs,gopherjs/gopherjs