Use fuel branch for Chalk

This makes sure we don't take too long in trait solving.

crates/ra_hir/src/ty/traits.rs

@@ -61,7 +61,7 @@ fn solve(
     let context = ChalkContext { db, krate };
     let solver = db.solver(krate);
     debug!("solve goal: {:?}", goal);
-    let solution = solver.lock().unwrap().solve(&context, goal);
+    let solution = solver.lock().unwrap().solve_with_fuel(&context, goal, Some(1000));
     debug!("solve({:?}) => {:?}", goal, solution);
     solution
 }