Update Android port

* doc/emacs/android.texi (Android Windowing): Reword
documentation.
* java/org/gnu/emacs/EmacsActivity.java (EmacsActivity):
* java/org/gnu/emacs/EmacsContextMenu.java (EmacsContextMenu):
* java/org/gnu/emacs/EmacsFontDriver.java (EmacsFontDriver):
* java/org/gnu/emacs/EmacsSdk7FontDriver.java
(EmacsSdk7FontDriver):
* java/org/gnu/emacs/EmacsService.java (queryBattery):
* java/org/gnu/emacs/EmacsWindow.java (EmacsWindow): Make
functions final and classes static where necessary.
* src/android.c (struct android_emacs_service): New method
`display_toast'.
(android_init_emacs_service): Load new method.
(android_display_toast): New function.
* src/android.h: Export.
* src/androidfns.c (Fandroid_detect_mouse):
* src/androidselect.c (Fandroid_clipboard_owner_p)
(Fandroid_set_clipboard, Fandroid_get_clipboard)
(Fandroid_browse_url): Prevent crashes when called from
libandroid-emacs.so.
* src/androidterm.c (handle_one_android_event): Fix out of date
commentary.

java/org/gnu/emacs/EmacsSdk7FontDriver.java

@@ -40,7 +40,7 @@ public class EmacsSdk7FontDriver extends EmacsFontDriver
   private static final String EM_STRING   = "m";
   private static final String TAG	  = "EmacsSdk7FontDriver";
 
-  protected class Sdk7Typeface
+  protected static final class Sdk7Typeface
   {
     /* The typeface and paint.  */
     public Typeface typeface;
@@ -164,7 +164,7 @@ public class EmacsSdk7FontDriver extends EmacsFontDriver
     }
   };
 
-  protected class Sdk7FontEntity extends FontEntity
+  protected static final class Sdk7FontEntity extends FontEntity
   {
     /* The typeface.  */
     public Sdk7Typeface typeface;
@@ -187,7 +187,7 @@ public class EmacsSdk7FontDriver extends EmacsFontDriver
     }
   };
 
-  protected class Sdk7FontObject extends FontObject
+  protected final class Sdk7FontObject extends FontObject
   {
     /* The typeface.  */
     public Sdk7Typeface typeface;