Check stalled coroutine obligations eagerly Fixes rust-lang/rust#151322 Fixes rust-lang/rust#151323 Fixes rust-lang/rust#137916 Fixes rust-lang/rust#138274 The problem is that stalled coroutine obligations can't be satisifed so that they cause normalization to fail in `mir_borrowck`. Thus, we failed to register any opaque to storage in the next solver. I fix it by checking these obligations earlier in `mir_borrowck`. r? @lcnr