Updating CTS tests.

The way the CTS tests were set up and switching system
settings before and after the tests was incorrect and
this was exposed due to a refactoring in the accessibility
manager service.

Tests for:https://googleplex-android-review.googlesource.com/#/c/271795/

bug:8153518

Change-Id: Ieeaf8fe6ea60fc7d88f8960a2fbc1ff0f535da2d
9 files changed