Auto merge of #48995 - aravind-pg:canonical-query, r=nikomatsakis

Create a canonical trait query for `evaluate_obligation`

This builds on the canonical query machinery introduced in #48411 to introduce a new canonical trait query for `evaluate_obligation` in the trait selector. Also ports most callers of the original `evaluate_obligation` to the new system (except in coherence, which requires support for intercrate mode). Closes #48537.

r? @nikomatsakis

diff --cc src/librustc/traits/fulfill.rs
Simple merge