Managed preferences for Chrome administrators

Implement support for managed preferences. This feature allows users (administrators) to easily change the default settings of the PDF Viewer for all Chrome or Chromium browsers within their organization.

External resources for end users (administrators)

- http://www.chromium.org/administrators/
- http://www.chromium.org/administrators/configuring-policy-for-extensions
- http://www.chromium.org/administrators/windows-quick-start
- http://www.chromium.org/administrators/mac-quick-start
- http://www.chromium.org/administrators/linux-quick-start
- http://www.chromium.org/administrators/policy-templates

Administrators can read one of the previous links to learn more about creating policies. We want to auto-generate these templates, but there are no public tools for doing that. It will be added in the future, see https://code.google.com/p/chromium/issues/detail?id=389061.

Resources for PDF.js/extension developers

- http://cs.chromium.org/file:policy_templates.json
- https://developer.chrome.com/extensions/manifest/storage