* Persist defaults to webPreferences object to JS land can read the inferred values instead of just user defined values
* Test inherited default propogation
* Refactor to remove coupling from fetching values and defaults
* Test description type
* Fix up tests
* This is to enable more browser-like behavior so that users who run third-party code
will not be DOS'ed with alerts and confirms. This is already handled like this
in most major browsers so this will greatly help these developers
When "sandboxed" is passed as a web preference for `BrowserWindow`, the newly
created renderer won't run any node.js code/integration, only communicating with
the system via the IPC API of the content module. This is a requirement for
running the renderer under chrome OS-level sandbox.
Beyond that, certain behaviors of AtomBrowserClient are modified when dealing
with sandboxed renderers:
- `OverrideSiteInstanceNavigation` no longer create a new `SiteInstance` for
every navigation. Instead, it reuses the source `SiteInstance` when not
navigating to a different site.
- `CanCreateWindow` will return true and allow javascript access.
