Position trailing NTB separator correctly for RTL mode.

Also moves the separator to have 8 DIP between its trailing edge and the NTB,
instead of between its leading edge and the NTB.  This parallels how it's
positioned when the tabs are drawing it in the other two NTB positions.

Bug: none
Test: Run with --force-ui-direction=rtl --new-tab-button-position=trailing and ensure a separator is visible next to the new tab button
Change-Id: I7e58485626c5ebab5dd477cefada5825479bdcb4
Reviewed-on: https://chromium-review.googlesource.com/1132484
Reviewed-by: Allen Bauer <kylixrd@chromium.org>
Commit-Queue: Peter Kasting <pkasting@chromium.org>
Cr-Commit-Position: refs/heads/master@{#574195}
1 file changed