When opening in the background, do not move the tab to front.

Remove some code which I assume was there for going to the
tab overview, and was incorrectly kept around.  When
opening a tab in the background, we do not need to set it
as the current tab.

Fixes http://b/issue?id=2118522

Change-Id: Ieaf512399b03307a1f70d952b648c0cfcf181c29
1 file changed