Fix crash on syn involving lifetimes returned by Chalk

If we get lifetime variables back in autoderef, just immediately replace
them by static lifetimes for now. Method resolution doesn't really deal
correctly with new variables being introduced (this needs to be fixed
more properly).

This fixes `rust-analyzer analysis-stats --with-deps` crashing in the RA
repo.

crates/hir_ty/src/method_resolution.rs

@@ -609,6 +609,7 @@ fn iterate_trait_method_candidates(
                 }
             }
             known_implemented = true;
+            // FIXME: we shouldn't be ignoring the binders here
             if callback(&self_ty.value, *item) {
                 return true;
             }