Fix ifdefs around INSTANTIATE_TEST_CASE_P in tab_drag_controller_interactive_uitest.cc

The tests were instantiated as
  #if ash && chromeos
  #elif ash
  #endif

Since we've droped USE_ASH form most configurations, this means tests
were no longer being instantiated anywhere except ChromeOS.

Review URL: https://codereview.chromium.org/1755513002

Cr-Commit-Position: refs/heads/master@{#378602}
1 file changed