input: tweak resize behavior to not change tab focus on border click
input: tweak resize behavior to not change tab focus on border click

If a resize is triggered on a tabbed or stacked container, change focus
to the tab which already had inactive focus, rather than to the tab
whose border was clicked -- otherwise, we'd change the active tab when
the user probably just wanted to resize.

1ace/sway,1ace/sway,1ace/sway