Cancelling the stateannouncer when entering button drop target

Change-Id: Ia10298e1d4862fc5f46894fa6d934207d6e9c117

src/com/android/launcher3/ButtonDropTarget.java

@@ -124,6 +124,9 @@ public abstract class ButtonDropTarget extends TextView
             mDrawable.setColorFilter(new ColorMatrixColorFilter(mCurrentFilter));
             setTextColor(mHoverColor);
         }
+        if (d.stateAnnouncer != null) {
+            d.stateAnnouncer.cancel();
+        }
         sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_SELECTED);
     }