Test cases for protected calls

test/contracts/bad_protected_call.aes

@@ -0,0 +1,6 @@
+contract Remote =
+  entrypoint id : int => int
+
+contract ProtectedCall =
+  entrypoint bad(r : Remote) =
+    r.id(protected = 0 == 1, 18)

test/contracts/protected_call.aes

@@ -0,0 +1,14 @@
+contract Remote =
+  entrypoint id : int => int
+
+contract ProtectedCall =
+
+  function higher_order(r : Remote) =
+    r.id
+
+  entrypoint test_ok(r : Remote) =
+    let f = higher_order(r)
+    let Some(n) = r.id(protected = true, 10)
+    let Some(m) = f(protected = true, 5)
+    n + m + r.id(protected = false, 100) + f(1)
+