Fix inaccurate description for crate and pathroot

compiler/rustc_resolve/src/diagnostics/impls.rs

@@ -2944,7 +2944,10 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
         };
         let scope = match &path[..failed_segment_idx] {
             [.., prev] => {
-                if prev.ident.name == kw::PathRoot {
+                if prev.ident.name == kw::PathRoot && self.tcx.sess.edition() > Edition::Edition2015
+                {
+                    format!("the list of imported crates")
+                } else if prev.ident.name == kw::PathRoot || prev.ident.name == kw::Crate {
                     format!("the crate root")
                 } else {
                     format!("`{}`", prev.ident)

tests/rustdoc-ui/issues/issue-61732.rs

@@ -1,4 +1,4 @@
 // This previously triggered an ICE.
 
 pub(in crate::r#mod) fn main() {}
-//~^ ERROR cannot find module or crate `r#mod` in `crate`
+//~^ ERROR cannot find module or crate `r#mod` in the crate root

tests/rustdoc-ui/issues/issue-61732.stderr

@@ -1,4 +1,4 @@
-error[E0433]: cannot find module or crate `r#mod` in `crate`
+error[E0433]: cannot find module or crate `r#mod` in the crate root
   --> $DIR/issue-61732.rs:3:15
    |
 LL | pub(in crate::r#mod) fn main() {}

tests/ui/imports/suggest-import-issue-120074.edition2015.stderr

@@ -1,4 +1,4 @@
-error[E0433]: cannot find `bar` in `crate`
+error[E0433]: cannot find `bar` in the crate root
   --> $DIR/suggest-import-issue-120074.rs:14:35
    |
 LL |     println!("Hello, {}!", crate::bar::do_the_thing);

tests/ui/imports/suggest-import-issue-120074.post2015.stderr

@@ -1,4 +1,4 @@
-error[E0433]: cannot find `bar` in `crate`
+error[E0433]: cannot find `bar` in the crate root
   --> $DIR/suggest-import-issue-120074.rs:14:35
    |
 LL |     println!("Hello, {}!", crate::bar::do_the_thing);

tests/ui/imports/suggest-import-issue-120074.rs

@@ -11,5 +11,5 @@ pub mod foo {
 }
 
 fn main() {
-    println!("Hello, {}!", crate::bar::do_the_thing); //~ ERROR cannot find `bar` in `crate`
+    println!("Hello, {}!", crate::bar::do_the_thing); //~ ERROR cannot find `bar` in the crate root
 }

tests/ui/resolve/editions-crate-root-2015.stderr

@@ -9,7 +9,7 @@ help: you might be missing a crate named `nonexistant`, add it to your project a
 LL + extern crate nonexistant;
    |
 
-error[E0433]: cannot find module or crate `nonexistant` in `crate`
+error[E0433]: cannot find module or crate `nonexistant` in the crate root
   --> $DIR/editions-crate-root-2015.rs:7:30
    |
 LL |     fn crate_inner(_: crate::nonexistant::Foo) {

tests/ui/resolve/editions-crate-root-2018.stderr

@@ -1,10 +1,10 @@
-error[E0433]: cannot find `nonexistant` in the crate root
+error[E0433]: cannot find `nonexistant` in the list of imported crates
   --> $DIR/editions-crate-root-2018.rs:4:26
    |
 LL |     fn global_inner(_: ::nonexistant::Foo) {
    |                          ^^^^^^^^^^^ could not find `nonexistant` in the list of imported crates
 
-error[E0433]: cannot find `nonexistant` in `crate`
+error[E0433]: cannot find `nonexistant` in the crate root
   --> $DIR/editions-crate-root-2018.rs:7:30
    |
 LL |     fn crate_inner(_: crate::nonexistant::Foo) {

tests/ui/resolve/path-suggestion-duplicated-crate-keyword.rs

@@ -8,7 +8,7 @@ pub mod unix {
         pub mod utils {
             pub fn f() {
                 let _x = crate::linux::system::Y;
-                //~^ ERROR cannot find `linux` in `crate`
+                //~^ ERROR cannot find `linux` in the crate root
             }
         }
         pub mod system {

tests/ui/resolve/path-suggestion-duplicated-crate-keyword.stderr

@@ -1,4 +1,4 @@
-error[E0433]: cannot find `linux` in `crate`
+error[E0433]: cannot find `linux` in the crate root
   --> $DIR/path-suggestion-duplicated-crate-keyword.rs:10:33
    |
 LL |                 let _x = crate::linux::system::Y;

tests/ui/resolve/visibility-indeterminate.stderr

@@ -4,7 +4,7 @@ error: cannot find macro `foo` in this scope
 LL | foo!();
    | ^^^
 
-error[E0433]: cannot find `bar` in the crate root
+error[E0433]: cannot find `bar` in the list of imported crates
   --> $DIR/visibility-indeterminate.rs:5:10
    |
 LL | pub(in ::bar) struct Baz {}

tests/ui/rfcs/rfc-2126-extern-absolute-paths/non-existent-2.stderr

@@ -1,4 +1,4 @@
-error[E0433]: cannot find `xcrate` in the crate root
+error[E0433]: cannot find `xcrate` in the list of imported crates
   --> $DIR/non-existent-2.rs:4:15
    |
 LL |     let s = ::xcrate::S;