Windows api mv3 sample (GoogleChrome#959)

* WIP windows API sample

* Update background.js

* Added mv3 windows API sample

* Corrections based on review

api-samples/windows/README.md

@@ -0,0 +1,14 @@
+# chrome.windows
+
+This sample demonstrates using the `chrome.windows` and `chrome.tabs` API to manage tabs across different windows.
+
+## Overview
+
+The extension interates across all tabs and moves them to the currently active window.
+
+## Running this extension
+
+1. Clone this repository.
+2. Load this directory in Chrome as an [unpacked extension](https://developer.chrome.com/docs/extensions/mv3/getstarted/development-basics/#load-unpacked).
+3. Make sure you have multiple windows of chrome open.
+4. Pin the extension and click on the action button.

api-samples/windows/background.js

@@ -0,0 +1,30 @@
+// Copyright 2023 Google LLC
+//
+// 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
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// 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.
+
+async function start() {
+  const current = await chrome.windows.getCurrent();
+
+  const allTabs = await chrome.tabs.query({});
+  allTabs.forEach((tab) => {
+    if (tab.windowId != current.id) {
+      chrome.tabs.move(tab.id, {
+        windowId: current.id,
+        index: tab.index
+      });
+    }
+  });
+}
+
+// Set up a click handler so that we can merge all the windows.
+chrome.action.onClicked.addListener(start);

api-samples/windows/manifest.json

@@ -0,0 +1,17 @@
+{
+  "name": "Merge Windows",
+  "version": "1.0.3",
+  "description": "Merges all of the browser's windows into the current window",
+  "icons": {
+    "48": "merge_windows_48.png",
+    "128": "merge_windows_128.png"
+  },
+  "background": {
+    "service_worker": "background.js"
+  },
+  "action": {
+    "default_icon": "arrow_in.png",
+    "default_title": "Merge Windows"
+  },
+  "manifest_version": 3
+}