Replace the no preview layout check with Resources.ID_NULL(0)

TODO: open up the RemoteViews(ApplicationInfo) API so that Launcher
      can inflate a layout from a work profile app.

Test: Before this CL, install tasks app in work profile. Observed
      crash when tapping Tasks header in the widgets picker.
      After this CL, no crash observed when tapping Tasks header in
      the widgets picker.

Bug: 181061277
Change-Id: I16c2b9aec5f4cabf15da35fea09f68c10797f5fa