1. UiTestAutomationBridge was accessing the root node in the
active window by tracking the accessibility event stream
and keeping the last active window changing event. Now
the bridge is stateless and the root node is fetched by
passing special window and view id with the request to
the system.
2. AccessibilityNodeInfos that are cached were not finished,
i.e. not sealed, causing exception when trying to access
their children or rpedecessors.
3. AccessibilityManagerService was not properly restoring its
state after the UI automation bridge disconnects from it.
I particular the devices was still in explore by touch mode
event if no services are enabled and the sutomation bridge
is disconnected.
4. ViewRootImpl for the focused window now fires accessibility
events when accessibility is enabled to allow accessibility
services to determine the current user location.
5. Several missing null checks in ViewRootImpl are fixed since
there were scenraios in which a NPE can occur.
6. Update the internal window content querying tests.
7. ViewRootImpl was firing one extra focus event.
bug:6009813
bug:6026952
Change-Id: Ib2e058d64538ecc268f9ef7a8f36ead047868a05
0d04e24553