[debugger] add more tests to side-effect free debug evaluate.

test/debugger/debug/debug-evaluate-no-side-effect-iife.js

+// Copyright 2017 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --ignition
+
+// Test that declaring local variables in IIFEs works with
+// side-effect free debug-evaluate.
+
+Debug = debug.Debug
+
+var exception = null;
+
+function listener(event, exec_state, event_data, data) {
+  if (event != Debug.DebugEvent.Break) return;
+  try {
+    function success(expectation, source) {
+      assertEquals(expectation,
+                   exec_state.frame(0).evaluate(source, true).value());
+    }
+    function fail(source) {
+      assertThrows(() => exec_state.frame(0).evaluate(source, true),
+                   EvalError);
+    }
+    // Declaring 'a' sets a property to the global object.
+    fail("var a = 3");
+    exec_state.frame(0).evaluate("var a = 2", false);
+    assertEquals(2, a);
+    // Wrapping into an IIFE would be fine, since 'a' is local.
+    success(100,
+            `(function(x) {
+                var a = 0;
+                for (var i = 0; i < x; i++) {
+                  a += x;
+                }
+                return a;
+              })(10);`);
+    success(100,
+            `(x => {
+                let a = 0;
+                for (var i = 0; i < x; i++) {
+                  a += x;
+                }
+                return a;
+              })(10);`);
+    // Not using 'var' to declare would make the access go to global object.
+    fail(   `(function(x) {
+                a = 0;
+                for (var i = 0; i < x; i++) {
+                  a += x;
+                }
+                return a;
+              })(10);`);
+  } catch (e) {
+    exception = e;
+    print(e, e.stack);
+  };
+};
+
+// Add the debug event listener.
+Debug.setListener(listener);
+
+function f() {
+  debugger;
+};
+
+f();
+
+assertNull(exception);