Add 83309

Issue: rust-lang/rust#83309

Author: fanninpm

ices/83309.rs

@@ -0,0 +1,22 @@
+fn main() {
+    for v in Query.iter_mut() {
+        *v -= 1;
+    }
+}
+
+pub struct Query;
+pub struct QueryIter<'a>(&'a i32);
+
+impl Query {
+    pub fn iter_mut<'a>(&'a mut self) -> QueryIter<'a> {
+        todo!();
+    }
+}
+
+impl<'a> Iterator for QueryIter<'a> {
+    type Item = &'a i32;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        todo!();
+    }
+}