Extract tests.

test/libsolidity/syntaxTests/constructor/constructor_visibility_old.sol

@@ -0,0 +1,13 @@
+// The constructor of a base class should not be visible in the derived class
+contract A { function A(string s) public { } }
+contract B is A {
+  function f() pure public {
+    A x = A(0); // convert from address
+    string memory y = "ab";
+    A(y); // call as a function is invalid
+    x;
+  }
+}
+// ----
+// Warning: (91-122): Defining constructors as functions with the same name as the contract is deprecated. Use "constructor(...) { ... }" instead.
+// TypeError: (244-248): Explicit type conversion not allowed from "string memory" to "contract A".