Add regression test

Author: oli-obk

src/test/ui/type-alias-impl-trait/implied_bounds3.rs

@@ -0,0 +1,18 @@
+// check-pass
+
+fn foo<F>(_: F)
+where
+    F: 'static,
+{
+}
+
+fn from<F: Send>(f: F) -> impl Send {
+    f
+}
+
+fn bar<T>() {
+    foo(from(|| ()))
+}
+
+fn main() {
+}