tests: Add flags/tab_skip test

This test verifies the behavior of tab_skip flag.

tests/tests/swfs/flags/README.md

@@ -0,0 +1,4 @@
+# Compatibility flags tests
+
+Warning: Outputs for these tests does not come from Flash Player!
+They are meant to test the behavior of Ruffle with flags incompatible with Flash Player.

tests/tests/swfs/flags/tab_skip/Test.as

@@ -0,0 +1,51 @@
+package {
+import flash.display.*;
+import flash.text.*;
+import flash.events.*;
+
+public class Test extends MovieClip {
+    private var obj1: TextField;
+    private var obj2: TextField;
+    private var obj3: TextField;
+
+    public function Test() {
+        stage.scaleMode = "noScale";
+
+        obj1 = new TextField();
+        obj1.type = "input";
+        obj1.border = true;
+        obj1.name = "obj1";
+        obj1.x = 70;
+        obj1.y = 10;
+        obj1.width = 10;
+        obj1.height = 10;
+
+        obj2 = new TextField();
+        obj2.type = "input";
+        obj2.border = true;
+        obj2.name = "obj2";
+        obj2.x = 10;
+        obj2.y = 20;
+        obj2.width = 10;
+        obj2.height = 10;
+
+        obj3 = new TextField();
+        obj3.type = "input";
+        obj3.border = true;
+        obj3.name = "obj3";
+        obj3.x = 40;
+        obj3.y = 40;
+        obj3.width = 10;
+        obj3.height = 10;
+
+        stage.focus = obj1;
+
+        for each (var obj in [obj1, obj2, obj3]) {
+            obj.addEventListener("focusIn", function (evt:FocusEvent):void {
+                trace("Focus changed: " + evt.relatedObject.name + " -> " + evt.target.name);
+            });
+            this.stage.addChild(obj);
+        }
+    }
+}
+}

tests/tests/swfs/flags/tab_skip/input.json

@@ -0,0 +1,6 @@
+[
+  { "type": "KeyDown", "key_code": 9 },
+  { "type": "KeyDown", "key_code": 9 },
+  { "type": "KeyDown", "key_code": 9 },
+  { "type": "KeyDown", "key_code": 9 }
+]

tests/tests/swfs/flags/tab_skip/output.txt

@@ -0,0 +1,4 @@
+Focus changed: obj1 -> obj2
+Focus changed: obj2 -> obj3
+Focus changed: obj3 -> obj1
+Focus changed: obj1 -> obj2

tests/tests/swfs/flags/tab_skip/test.toml

@@ -0,0 +1,3 @@
+num_ticks = 1
+
+flags = "-tab_skip"