Ensure that the Application is constructed before any Service.

This fixes dependency injection issues and brings Service construction
in line with the way that Activities are created. Specifically, this
ensures that there is always a reference to a Context available at
the time a Service is constructed, such that the Context can then be
injected into the constructor of the Service.

Bug: 140868981
Test: atest SystemUITests
Change-Id: If85e4106fef8c2fd12f7ca9e8b7fd686af62e29b