ChromeOS Mojo Services and Allowlisting for IWAs

This directory hosts the Mojo services for features restricted to allowlisted Isolated Web Apps (IWAs) on ChromeOS.

Currently, it implements the window.setShape API.

• The Blink frontend lives in //third_party/blink/renderer/modules/set_shape/.
• The browser tests verifying this API and its allowlist behavior live in //chrome/browser/ash/set_shape/.