Touch exploration feature, event bubling, refactor

1. Added an Input Filter that interprets the touch screen motion
   events to perfrom accessibility exploration. One finger explores.
   Tapping within a given time and distance slop on the last exlopred
   location does click and long press, respectively. Two fingers close
   and in the same diretion drag. Multiple finglers or two fingers in
   different directions or two fingers too far away are delegated to
   the view hierarchy. Non moving fingers "accidentally grabbed the
   device for the scrren" are ignored.

2. Added accessibility events for hover enter, hover exit, touch
   exoloration gesture start, and end. Accessibility hover events
   are fired by the hover pipeline. An accessibility event is
   dispatched up the view tree and the topmost view fires it.
   Thus predecessors can augment the fired event. An accessibility
   event has several records and a predecessor can optionally
   modify, delete, and add such to the event.

3. Added onPopulateAccessibilityEvent and refactored the existing
   accessibility code to use it.

4. Added API for querying the currently enabled accessibility services
   by feedback type.

Change-Id: Iec03c6c3fe298de3f14cb6efdbb9b198cd531a0c

1 files changed, 17 insertions, 2 deletions

diff --git a/core/java/android/view/InputEventConsistencyVerifier.java b/core/java/android/view/InputEventConsistencyVerifier.java
index b5ca2c2a8c1c..e14b97558e49 100644
--- a/core/java/android/view/InputEventConsistencyVerifier.java
+++ b/core/java/android/view/InputEventConsistencyVerifier.java
@@ -30,7 +30,6 @@ import android.util.Log;
  * @hide
  */
 public final class InputEventConsistencyVerifier {
-    private static final String TAG = "InputEventConsistencyVerifier";
     private static final boolean IS_ENG_BUILD = "eng".equals(Build.TYPE);
 
     // The number of recent events to log when a problem is detected.
@@ -44,6 +43,11 @@ public final class InputEventConsistencyVerifier {
     // Consistency verifier flags.
     private final int mFlags;
 
+    // Tag for logging which a client can set to help distinguish the output
+    // from different verifiers since several can be active at the same time.
+    // If not provided defaults to the simple class name.
+    private final String mLogTag;
+
     // The most recently checked event and the nesting level at which it was checked.
     // This is only set when the verifier is called from a nesting level greater than 0
     // so that the verifier can detect when it has been asked to verify the same event twice.
@@ -103,8 +107,19 @@ public final class InputEventConsistencyVerifier {
      * @param flags Flags to the verifier, or 0 if none.
      */
     public InputEventConsistencyVerifier(Object caller, int flags) {
+        this(caller, flags, InputEventConsistencyVerifier.class.getSimpleName());
+    }
+
+    /**
+     * Creates an input consistency verifier.
+     * @param caller The object to which the verifier is attached.
+     * @param flags Flags to the verifier, or 0 if none.
+     * @param logTag Tag for logging. If null defaults to the short class name.
+     */
+    public InputEventConsistencyVerifier(Object caller, int flags, String logTag) {
         this.mCaller = caller;
         this.mFlags = flags;
+        this.mLogTag = (logTag != null) ? logTag : "InputEventConsistencyVerifier";
     }
 
     /**
@@ -596,7 +611,7 @@ public final class InputEventConsistencyVerifier {
                 }
             }
 
-            Log.d(TAG, mViolationMessage.toString());
+            Log.d(mLogTag, mViolationMessage.toString());
             mViolationMessage.setLength(0);
             tainted = true;
         }