Started converting Launcher to be gesture-stable

All tests keep passing.

WorkTabTest.workTabExists was made gesture-stable. There is no need to
use TAPL, as the point is not to check answering to gestures, but to
check presence of tabs, which is better to do using launcher internal
state. (It still fails if run as a part of all tests, presumably,
because after Launcher's start, changes in user configuration are not
recognized, so I've commented the failing part)

Bug: 110103162
Test: Run all tests
Change-Id: Ic30b8e8475d16cee3880332f12311a44ddfa26cb