Rearrange Android splash screen messages

Rearrange Android splash screen messages

* lisp/startup.el (fancy-startup-tail, fancy-startup-screen)
(normal-splash-screen): Adjust for function renaming; move the
storage permissions notice to the top of the splash screen.

* lisp/term/android-win.el (android-after-splash-screen): Rename
from android-before-splash-screen and adjust layout lightly.

* src/android.c (android_wc_lookup_string): Terminate character
composition after a character is returned, whether it contain a
Unicode character or not.