This is a bug report.

**Expected Behavior**
React should not suggest me to download the DevTools extension in a `chrome-extension://` page, because the extension has no permission to inject the devtool.

**Actual Behavior**
`Download the React DevTools and use an HTTP server (instead of a file: URL) for a better development experience: https://fb.me/react-devtools`

**Reproducing**

1. Create a Chrome extension with an `option` or `popup` page that uses React
2. Load the extension to Chrome and open up that page.
3. Observe console.

**Version**
Google Chrome 56.0.2924.3
React 15.4.0

canHydrateTextInstance(
    instance: Instance | TextInstance,
    text: string,
  ): boolean {
    if (text === '') {
      
      return false;
    }
    return instance.nodeType === TEXT_NODE;
  },
  getNextHydratableSibling(
    instance: Instance | TextInstance,
  ): null | Instance | TextInstance {
    let node = instance.nextSibling;
    
    while (
      node &&
      node.nodeType !== ELEMENT_NODE &&
      node.nodeType !== TEXT_NODE
    ) {
      node = node.nextSibling;
    }
    return (node: any);
  },
  getFirstHydratableChild(
    parentInstance: Container | Instance,
  ): null | Instance | TextInstance {
    let next = parentInstance.firstChild;
    
    while (