Update Android port

Update Android port

* lisp/tool-bar.el (modifier-bar-modifier-list): New variable.
(modifier-bar-button): New function.
(tool-bar-event-apply-alt-modifier)
(tool-bar-event-apply-super-modifier)
(tool-bar-event-apply-hyper-modifier)
(tool-bar-event-apply-shift-modifier)
(tool-bar-event-apply-control-modifier)
(tool-bar-event-apply-meta-modifier): Factor out modifier bar
logic to that function, and redisplay the tool bar where
necessary.
(modifier-bar-available-p): New function.
(modifier-bar-mode): Disable tool bar items corresponding to
modifier keys that've already been pressed.

* etc/images/shift.pbm: Regenerate from correct font.