Inconsistent events on transition from gesture detection to touch exploration.

1. The problem is that we have a gesture detection timeout after which we transition
   to touch exploration state. This handles the case where the user is using too high
   velocity while trying to touch explore. The delayed command that transitions from
   gesture detection state to touch exploration state was not firing an event for the
   end of gesture detection and begin of touch exploration before doing its main work
   to transition to touch exploring state.

bug:7233819

Change-Id: I5c4855231aa3826dadbee324e74a3c9e52c96cd9

Author: sganov

services/java/com/android/server/accessibility/TouchExplorer.java

@@ -1300,6 +1300,11 @@ public void remove() {
 
         @Override
         public void run() {
+            // Announce the end of gesture recognition.
+            sendAccessibilityEvent(AccessibilityEvent.TYPE_GESTURE_DETECTION_END);
+            // Clearing puts is in touch exploration state with a finger already
+            // down, so announce the transition to exploration state.
+            sendAccessibilityEvent(AccessibilityEvent.TYPE_TOUCH_EXPLORATION_GESTURE_START);
             clear();
         }
     }