Moving resources out of ResourceConfiguration.

- We can no longer make assumptions about the ability to
  get resources for the RecentsActivity before the activity
  is launched (the configuration of the launched activity
  can differ than the current configuration if a window
  is docked).  As such, we reduce RecentsConfiguration
  to the set of values that are context agnostic, or can
  be calculated directly given an application context.
  This ensures that we will continue to be able to compute
  the target task bounds given any context.

Change-Id: I423c90635eb294aa2d78a6f56771b98ee2b9d5e4