Google Chrome App Launcher does only appear in the taskbar or dock if you install a desktop app from the Chrome WebShop. Here is how to add it without installing a desktop app. Even when you sync a desktop app from another installment (with the same chrome login) it doesn't appear.
- Windows: To repin the App Launcher to the taskbar click the Start menu > All programs > Google Chrome> hover over "Chrome App Launcher" > right click and click Pin to Taskbar.
- Mac: Drag the Chrome App Launcher app from Finder, or the Spotlight results list, to your Dock.