Improve non_fmt_panics suggestion based on trait impls.
diff --git a/Cargo.lock b/Cargo.lock
index 9406089..30b59d7 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3932,6 +3932,7 @@
  "rustc_feature",
  "rustc_hir",
  "rustc_index",
+ "rustc_infer",
  "rustc_middle",
  "rustc_parse_format",
  "rustc_serialize",