Remove ImplItemKind::OpaqueTy from clippy

Author: matthewjasper

src/tools/clippy/clippy_lints/src/missing_doc.rs

@@ -187,7 +187,6 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingDoc {
             hir::ImplItemKind::Const(..) => "an associated constant",
             hir::ImplItemKind::Fn(..) => "a method",
             hir::ImplItemKind::TyAlias(_) => "an associated type",
-            hir::ImplItemKind::OpaqueTy(_) => "an existential type",
         };
         self.check_missing_docs_attrs(cx, &impl_item.attrs, impl_item.span, desc);
     }

src/tools/clippy/clippy_lints/src/missing_inline.rs

@@ -142,7 +142,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingInline {
 
         let desc = match impl_item.kind {
             hir::ImplItemKind::Fn(..) => "a method",
-            hir::ImplItemKind::Const(..) | hir::ImplItemKind::TyAlias(_) | hir::ImplItemKind::OpaqueTy(_) => return,
+            hir::ImplItemKind::Const(..) | hir::ImplItemKind::TyAlias(_) => return,
         };
 
         let def_id = cx.tcx.hir().local_def_id(impl_item.hir_id);

src/tools/clippy/clippy_lints/src/utils/inspector.rs

@@ -63,7 +63,6 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for DeepCodeInspector {
             },
             hir::ImplItemKind::Fn(..) => println!("method"),
             hir::ImplItemKind::TyAlias(_) => println!("associated type"),
-            hir::ImplItemKind::OpaqueTy(_) => println!("existential type"),
         }
     }
     // fn check_trait_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx