Fixing bad refactoring of orientation calculation.

- The orientation needs to be calculated from the screen width/height,
  which are set below the current calculation of the orientation (whoops).
  This bug was introduced in ag/1905010 and causes extra configuration
  changes due to the configuration orientation being set correctly before
  it is corrected on the next change (at the end of the transition).

Bug: 36099204
Test: android.server.cts.ActivityManagerPinnedStackTests
Change-Id: Ieca1f73fe61fc1dcea106535c019b52d126b8743