tests: add message call benchmark (#717)

Co-authored-by: Federico Kunze Küllmer <31522760+fedekunze@users.noreply.github.com>

tests/solidity/suites/basic/contracts/TestMessageCall.sol

@@ -0,0 +1,25 @@
+pragma solidity 0.5.17;
+
+contract Inner {
+    event TestEvent(uint256);
+    function test() public returns (uint256) {
+        emit TestEvent(42);
+        return 42;
+    }
+}
+
+contract TestMessageCall {
+    Inner _inner;
+    constructor() public {
+        _inner = new Inner();
+    }
+
+    // benchmarks
+    function benchmarkMessageCall(uint iterations) public returns (uint256) {
+        uint256 n = 0;
+        for (uint i=0; i < iterations; i++) {
+            n += _inner.test();
+        }
+        return n;
+    }
+}