Added virtual view hierarchy for keyboard accessibility.

java/Android.mk

...nputmethod/accessibility/AccessibilityEntityProvider.java

...android/inputmethod/accessibility/AccessibilityUtils.java

...nputmethod/accessibility/AccessibleKeyboardViewProxy.java

...droid/inputmethod/accessibility/FlickGestureDetector.java

...d/inputmethod/accessibility/KeyCodeDescriptionMapper.java

...oid/inputmethod/compat/AccessibilityEventCompatUtils.java

...d/inputmethod/compat/AccessibilityManagerCompatUtils.java

...om/android/inputmethod/compat/MotionEventCompatUtils.java

...com/android/inputmethod/compat/ViewParentCompatUtils.java

...rc/com/android/inputmethod/keyboard/KeyboardSwitcher.java

...c/com/android/inputmethod/keyboard/LatinKeyboardView.java