make move unwrap_binder! a move subpath

Author: beepster4096

compiler/rustc_mir_dataflow/src/move_paths/builder.rs

@@ -222,6 +222,7 @@ impl<'a, 'tcx, F: Fn(Ty<'tcx>) -> bool> MoveDataBuilder<'a, 'tcx, F> {
                             _ => bug!("Unexpected type {:#?}", place_ty.is_array()),
                         },
                         MoveSubPath::Downcast(_) => (),
+                        MoveSubPath::UnwrapUnsafeBinder => (),
                     };
 
                     move_elem

compiler/rustc_mir_dataflow/src/move_paths/mod.rs

@@ -396,6 +396,7 @@ pub enum MoveSubPath {
     Field(FieldIdx),
     ConstantIndex(u64),
     Downcast(VariantIdx),
+    UnwrapUnsafeBinder,
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
@@ -416,10 +417,12 @@ impl MoveSubPath {
                 MoveSubPath::ConstantIndex(offset)
             }
             ProjectionKind::Downcast(_, idx) => MoveSubPath::Downcast(idx),
+            ProjectionKind::UnwrapUnsafeBinder(_) => MoveSubPath::UnwrapUnsafeBinder,
 
-            // these should be the same move path as their parent
-            // they're fine to skip because they cannot have sibling move paths
-            ProjectionKind::OpaqueCast(_) | ProjectionKind::UnwrapUnsafeBinder(_) => {
+            // this should be the same move path as its parent
+            // its fine to skip because it cannot have sibling move paths
+            // and it is not a user visible path
+            ProjectionKind::OpaqueCast(_) => {
                 return MoveSubPathResult::Skip;
             }