Add ICE 78652

Author: oliviacrain

ices/78652.rs

@@ -0,0 +1,11 @@
+#![unstable(feature = "humans", issue = "none")]
+#![feature(staged_api)]
+struct Foo;
+impl Foo {
+    #[stable(feature = "rust1", since = "1.0.0")]
+    const fn gated() -> u32 {
+        42
+    }
+}
+
+fn main() {}