fix: add missing files

lib/src/main/java/com/microsoft/playwright/Deferred.java

@@ -0,0 +1,21 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ * <p>
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.microsoft.playwright;
+
+public interface Deferred<T> {
+  T get();
+}

lib/src/main/java/com/microsoft/playwright/Listener.java

@@ -0,0 +1,21 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ * <p>
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.microsoft.playwright;
+
+public interface Listener<T> {
+  void handle(T event);
+}

lib/src/test/resources/offscreenbuttons.html

@@ -0,0 +1,55 @@
+<style>
+  button {
+    position: absolute;
+    width: 100px;
+    height: 20px;
+    margin: 0;
+  }
+
+  body, html {
+    margin: 0;
+    padding: 0;
+    height: 100%;
+    width: 100%;
+    position: relative;
+  }
+
+  div {
+    position: absolute;
+    left: 0;
+    top: 0;
+    right: 0;
+    bottom: 0;
+  }
+
+  #btn0 { right: 0px; top: 0; }
+  #btn1 { right: -10px; top: 25px; }
+  #btn2 { right: -20px; top: 50px; }
+  #btn3 { right: -30px; top: 75px; }
+  #btn4 { right: -40px; top: 100px; }
+  #btn5 { right: -50px; top: 125px; }
+  #btn6 { right: -60px; top: 150px; }
+  #btn7 { right: -70px; top: 175px; }
+  #btn8 { right: -80px; top: 200px; }
+  #btn9 { right: -90px; top: 225px; }
+  #btn10 { right: -100px; top: 250px; }
+</style>
+<div>
+<button id=btn0>0</button>
+<button id=btn1>1</button>
+<button id=btn2>2</button>
+<button id=btn3>3</button>
+<button id=btn4>4</button>
+<button id=btn5>5</button>
+<button id=btn6>6</button>
+<button id=btn7>7</button>
+<button id=btn8>8</button>
+<button id=btn9>9</button>
+<button id=btn10>10</button>
+</div>
+<script>
+window.addEventListener('DOMContentLoaded', () => {
+  for (const button of Array.from(document.querySelectorAll('button')))
+    button.addEventListener('click', () => console.log('button #' + button.textContent + ' clicked'), false);
+}, false);
+</script>