Summary:
This is a replacement for PR https://github.com/facebook/flipper/pull/1486 which had the wrong username
When the network plugin is loaded, the route table in the device is empty. It needs to be populated with whatever routes have already been created and saved in local storage. Otherwise, the user would need to modify the routes to force an update.
Issue is described here - https://github.com/facebook/flipper/issues/1476
## Changelog
Routes updated in device when plugin is initialized
Pull Request resolved: https://github.com/facebook/flipper/pull/1491
Test Plan:
1. Create a mock for the get request in the sample Android app
2. Kill the app
3. Start the app
4. Issue the get request in the app
5. Verify that the request is mocked in the Network plugin

Reviewed By: passy
Differential Revision: D23292355
Pulled By: mweststrate
fbshipit-source-id: 2fe16e9067a627cae02a4b1db422952d364fd036