Add ShortcutsLaunchTest and ShortcutsToHomeTest.

- ShortcutsLaunchTest verifies that launching shortcut
  from the deep shortcuts container works.
- ShortcutsToHomeTest verifies that shortcuts can be
  dragged from the deep shortcuts container.

Change-Id: I6919b69d4ea1c9e0f13a8f236266745c12ef0715