Move long press shift handling from PointerTracker to KeyboardState

This change also
  * Rename phone shift keyboard to phone symbols keyboard.
    Use CODE_SWITCH_ALPHA_SYMBOL code to switch between phone and phone symbols keyboard.
  * Remove phone symbols keyboard from tablet.
  * Introduces enableLongPress flag of Key.keyActionFlags attribute.
  * Remove clumsy long press code from PointerTracker.
  * Remove CODE_CAPSLOCK handling from LatinIME.
  * Make KeyboardSwitcher to invoke haptic and audio feedback.

Change-Id: I00e1f697a10ab5112aec75e36853b96246ff5054