fix focus indication on "Move Outcome" modal
fix focus indication on "Move Outcome" modal

Fixes: CNVS-26058

test plan:
- as an admin using the old or new ui
- navigate to the outcomes tab within a course
- click onto an outcome
- click the "move outcome" or "move outcome group" button
  that will launch the move outcome modal
- the outcome tree should now have the standard browser focus
  indicator (see example: http://screencast.com/t/I1SVK1URcz)
- switch ui version to ensure the same happens in the other ui

Change-Id: Ief1721f2dee3150c30dec28918eb9ebfcc692df9
Reviewed-on: https://gerrit.instructure.com/71243
Tested-by: Jenkins
Reviewed-by: Chris Hart <b82b40b84a2f06957ec9caf1768340bd6b929cc4@instructure.com>
Product-Review: Chris Hart <b82b40b84a2f06957ec9caf1768340bd6b929cc4@instructure.com>
QA-Review: Myller de Araujo <e5c7c5e1b7f2ce5e9870cc98ec52b20b3006cb48@instructure.com>

sfu/canvas-lms,djbender/canvas-lms,SwinburneOnline/canvas-lms,djbender/canvas-lms,djbender/canvas-lms,roxolan/canvas-lms,HotChalk/canvas-lms,grahamb/canvas-lms,venturehive/canvas-lms,SwinburneOnline/canvas-lms,SwinburneOnline/canvas-lms,matematikk-mooc/canvas-lms,roxolan/canvas-lms,fronteerio/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,fronteerio/canvas-lms,HotChalk/canvas-lms,djbender/canvas-lms,HotChalk/canvas-lms,roxolan/canvas-lms,HotChalk/canvas-lms,matematikk-mooc/canvas-lms,venturehive/canvas-lms,grahamb/canvas-lms,dgynn/canvas-lms,matematikk-mooc/canvas-lms,instructure/canvas-lms,venturehive/canvas-lms,dgynn/canvas-lms,matematikk-mooc/canvas-lms,instructure/canvas-lms,sfu/canvas-lms,sfu/canvas-lms,instructure/canvas-lms,SwinburneOnline/canvas-lms,grahamb/canvas-lms,sfu/canvas-lms,grahamb/canvas-lms,roxolan/canvas-lms,fronteerio/canvas-lms,fronteerio/canvas-lms,dgynn/canvas-lms,instructure/canvas-lms,dgynn/canvas-lms,sfu/canvas-lms,grahamb/canvas-lms,instructure/canvas-lms,venturehive/canvas-lms