chromium/extensions/test/data/app_view/apitest/media_request/manifest.json

{
  "manifest_version": 2,
  "name": "WebView Media request test",
  "version": "1",
  "app": {
    "background": {
      "scripts": ["test.js"]
    }
  },
  "permissions": [
    "webview",
    "audioCapture",
    "videoCapture"
  ],
  "webview": {
    "partitions": [
      {
        "name": "media",
        "accessible_resources": ["guest.html"]
      }
    ]
  }
}