CrOS status area: Revert order for adding child views

This allows focus traversal to match visual order.

Instead of adding child views right to left, and then adding views to
the layout from last to first, this adds child views from left to
right, and then adds them to the layout from first to last. That way,
the visual order doesn't change, but using "Tab" to navigate through
views goes from left to right as in other parts of the system.

Bug: 854319, 753409
Change-Id: Icadb64a0baf714c62110af9b4627feb9e3a5fe36
Reviewed-on: https://chromium-review.googlesource.com/c/1474889
Reviewed-by: Tetsui Ohkubo <tetsui@chromium.org>
Commit-Queue: Manu Cornet <manucornet@chromium.org>
Cr-Commit-Position: refs/heads/master@{#633120}
2 files changed