GitLab

App Delegate conversion:
* Removed Application.Delegate
* Convert DesktopRemoting and AppRemoting to be subclasses of Application
* Add ApplicationInterface so that jscompile can verify all required overrides are provided.

Access to SessionConnector was a big motivation for having the apps as a subclass:
* Create the SessionConnector in the constructor rather than in the getter.
* Remove some references to remoting.app.getSessionConnector

Test updates:
* Updated base.inherits unittests to verify calling superclass methods with arguments.
* Removed desktopDelegateForTesting since we can use remoting.app for that now.

BUG=465878

Review URL: https://codereview.chromium.org/1016373003

Cr-Commit-Position: refs/heads/master@{#322437}