[SMTChecker] Fix calls to virtual/overriden functions

test/libsolidity/smtCheckerTests/functions/super_function_assert.sol

@@ -0,0 +1,32 @@
+pragma experimental SMTChecker;
+contract A {
+	int x = 0;
+
+	function f() virtual internal {
+		x = 2;
+	}
+
+	function proxy() public {
+		f();
+	}
+}
+
+contract C is A {
+	function f() internal virtual override {
+		super.f();
+		assert(x == 2);
+		assert(x == 3); // should fail
+	}
+}
+
+contract D is C {
+
+	function f() internal override {
+		super.f();
+		assert(x == 2);
+		assert(x == 3); // should fail
+	}
+}
+// ----
+// Warning 6328: (237-251): CHC: Assertion violation happens here.\nCounterexample:\nx = 2\n\n\n\nTransaction trace:\nconstructor()\nState: x = 0\nproxy()
+// Warning 6328: (360-374): CHC: Assertion violation happens here.\nCounterexample:\nx = 2\n\n\n\nTransaction trace:\nconstructor()\nState: x = 0\nproxy()

test/libsolidity/smtCheckerTests/functions/virtual_function_assert.sol

@@ -0,0 +1,21 @@
+pragma experimental SMTChecker;
+contract A {
+    int x = 0;
+
+    function f() virtual internal view {
+        assert(x == 0);
+    }
+
+    function proxy() public view {
+        f();
+    }
+}
+
+contract C is A {
+
+    function f() internal view override {
+        assert(x == 1);
+    }
+}
+// ----
+// Warning 6328: (259-273): CHC: Assertion violation happens here.\nCounterexample:\nx = 0\n\n\n\nTransaction trace:\nconstructor()\nState: x = 0\nproxy()