rustc_middle: Remove trait `DefIdTree`

This trait was a way to generalize over both `TyCtxt` and `Resolver`, but now `Resolver` has access to `TyCtxt`, so this trait is no longer necessary.

3 files changed, 1 insertions, 3 deletions

diff --git a/clippy_lints/src/methods/bind_instead_of_map.rs b/clippy_lints/src/methods/bind_instead_of_map.rs
index 4720a6e6888..8e1130cf8df 100644
--- a/clippy_lints/src/methods/bind_instead_of_map.rs
+++ b/clippy_lints/src/methods/bind_instead_of_map.rs
@@ -8,7 +8,6 @@ use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, CtorOf, DefKind, Res};
 use rustc_hir::{LangItem, QPath};
 use rustc_lint::LateContext;
-use rustc_middle::ty::DefIdTree;
 use rustc_span::Span;
 
 pub(crate) struct OptionAndThenSome;
diff --git a/clippy_lints/src/methods/chars_cmp.rs b/clippy_lints/src/methods/chars_cmp.rs
index 56b7fbb9d4b..079df2226d1 100644
--- a/clippy_lints/src/methods/chars_cmp.rs
+++ b/clippy_lints/src/methods/chars_cmp.rs
@@ -6,7 +6,7 @@ use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_lint::LateContext;
 use rustc_lint::Lint;
-use rustc_middle::ty::{self, DefIdTree};
+use rustc_middle::ty;
 
 /// Wrapper fn for `CHARS_NEXT_CMP` and `CHARS_LAST_CMP` lints.
 pub(super) fn check(
diff --git a/clippy_lints/src/methods/option_map_or_none.rs b/clippy_lints/src/methods/option_map_or_none.rs
index 3a23ecc50dc..41ceef19e3a 100644
--- a/clippy_lints/src/methods/option_map_or_none.rs
+++ b/clippy_lints/src/methods/option_map_or_none.rs
@@ -6,7 +6,6 @@ use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_hir::LangItem::{OptionNone, OptionSome};
 use rustc_lint::LateContext;
-use rustc_middle::ty::DefIdTree;
 use rustc_span::symbol::sym;
 
 use super::OPTION_MAP_OR_NONE;