Auto merge of #106458 - albertlarsan68:move-tests, r=jyn514

Move src/test to the root

See MCP at rust-lang/compiler-team#573

There may be more changes needed.

The first commit is just the move of the files:
You can check that the first commit did not do anything else than renames by running
```
git diff --diff-filter=r -M100% <rust-lang remote>/master <first commit hash>
```
The output should be empty, because the filter excludes renames, and the match threshold for qualifying a rename is 100%.

The second one is mostly a "find and replace" of `src/test` to `tests` and whatever is needed to make CI pass.

What is left to do:
---

- [x] Move directory
- [ ] Change references to `src/test`
    - [x] Change references in-tree
    - [ ] Change references in submodules / out-of-tree docs
- [x] Make CI pass:
    - [x] Fix tidy
    - [x] Fix tests
    - [x] Bless tests if needed (shouldn't normally)
- [ ] Merge it !

1 files changed, 54 insertions, 0 deletions

diff --git a/tests/ui/class-cast-to-trait.rs b/tests/ui/class-cast-to-trait.rs
new file mode 100644
index 00000000000..345d6efd2d9
--- /dev/null
+++ b/tests/ui/class-cast-to-trait.rs
@@ -0,0 +1,54 @@
+trait Noisy {
+  fn speak(&self);
+}
+
+struct Cat {
+  meows : usize,
+
+  how_hungry : isize,
+  name : String,
+}
+
+impl Cat {
+  pub fn eat(&self) -> bool {
+    if self.how_hungry > 0 {
+        println!("OM NOM NOM");
+        self.how_hungry -= 2;
+        return true;
+    }
+    else {
+        println!("Not hungry!");
+        return false;
+    }
+  }
+}
+
+impl Noisy for Cat {
+  fn speak(&self) { self.meow(); }
+
+}
+
+impl Cat {
+    fn meow(&self) {
+      println!("Meow");
+      self.meows += 1;
+      if self.meows % 5 == 0 {
+          self.how_hungry += 1;
+      }
+    }
+}
+
+fn cat(in_x : usize, in_y : isize, in_name: String) -> Cat {
+    Cat {
+        meows: in_x,
+        how_hungry: in_y,
+        name: in_name
+    }
+}
+
+
+
+fn main() {
+  let nyan: Box<dyn Noisy> = Box::new(cat(0, 2, "nyan".to_string())) as Box<dyn Noisy>;
+  nyan.eat(); //~ ERROR no method named `eat` found
+}