Update Android port

* .gitignore: Add new files.
* INSTALL.android: Explain how to build Emacs for ancient
versions of Android.
* admin/merge-gnulib (GNULIB_MODULES): Add getdelim.
* build-aux/config.guess (timestamp, version):
* build-aux/config.sub (timestamp, version): Autoupdate.
* configure.ac (BUILD_DETAILS, ANDROID_MIN_SDK):
(ANDROID_STUBIFY): Allow specifying CFLAGS via ANDROID_CFLAGS.
Add new configure tests for Android API version when not
explicitly specified.

* doc/emacs/android.texi (Android): Add reference to ``Other
Input Devices''.
(Android File System): Remove restrictions on directory-files on
the assets directory.
* doc/emacs/emacs.texi (Top): Add Other Input Devices to menu.
* doc/emacs/input.texi (Other Input Devices): New node.
* doc/lispref/commands.texi (Touchscreen Events): Document
changes to touchscreen input events.
* doc/lispref/frames.texi (Pop-Up Menus): Likewise.
* etc/NEWS: Announce changes.
* java/Makefile.in: Use lib-src/asset-directory-tool to generate
an `directory-tree' file placed in /assets.
* java/debug.sh: Large adjustments to support Android 2.2 and
later.

* java/org/gnu/emacs/EmacsContextMenu.java (inflateMenuItems):
* java/org/gnu/emacs/EmacsCopyArea.java (perform):
* java/org/gnu/emacs/EmacsDialog.java (toAlertDialog):
* java/org/gnu/emacs/EmacsDrawLine.java (perform):
* java/org/gnu/emacs/EmacsDrawRectangle.java (perform):
* java/org/gnu/emacs/EmacsDrawable.java (EmacsDrawable):
* java/org/gnu/emacs/EmacsFillPolygon.java (perform):
* java/org/gnu/emacs/EmacsFillRectangle.java (perform):
* java/org/gnu/emacs/EmacsGC.java (EmacsGC):
* java/org/gnu/emacs/EmacsPixmap.java (EmacsPixmap):
(destroyHandle):
* java/org/gnu/emacs/EmacsSdk7FontDriver.java (draw): Avoid
redundant canvas saves and restores.
* java/org/gnu/emacs/EmacsService.java (run):
* java/org/gnu/emacs/EmacsView.java (EmacsView):
(handleDirtyBitmap):
* java/org/gnu/emacs/EmacsWindow.java (changeWindowBackground)
(EmacsWindow): Make compatible with Android 2.2 and later.

* lib-src/Makefile.in (DONT_INSTALL): Add asset-directory-tool
on Android.:(asset-directory-tool{EXEEXT}): New target.
* lib-src/asset-directory-tool.c (struct directory_tree, xmalloc)
(main_1, main_2, main): New file.

* lib, m4: Merge from gnulib.  This will be reverted before
merging to master.

* lisp/button.el (button-map):
(push-button):
* lisp/frame.el (display-popup-menus-p): Improve touchscreen
support.
* lisp/subr.el (event-start):
(event-end): Handle touchscreen events.
* lisp/touch-screen.el (touch-screen-handle-timeout):
(touch-screen-handle-point-update):
(touch-screen-handle-point-up):
(touch-screen-track-tap):
(touch-screen-track-drag):
(touch-screen-drag-mode-line-1):
(touch-screen-drag-mode-line): New functions.
([mode-line touchscreen-begin]):
([bottom-divider touchscreen-begin]): Bind new events.

* lisp/wid-edit.el (widget-event-point):
(widget-keymap):
(widget-event-start):
(widget-button--check-and-call-button):
(widget-button-click): Improve touchscreen support.

* src/alloc.c (make_lisp_symbol): Avoid ICE on Android NDK GCC.
(mark_pinned_symbols): Likewise.

* src/android.c (struct android_emacs_window): New struct.
(window_class): New variable.
(android_run_select_thread): Add workaround for Android platform
bug.
(android_extract_long, android_scan_directory_tree): New
functions.
(android_file_access_p): Use those functions instead.
(android_init_emacs_window): New function.
(android_init_emacs_gc_class): Update signature of `markDirty'.
(android_change_gc, android_set_clip_rectangles): Tell the GC
whether or not clip rects were dirtied.
(android_swap_buffers): Do not look up method every time.
(struct android_dir): Adjust for new directory tree lookup.
(android_opendir, android_readdir, android_closedir): Likewise.
(android_four_corners_bilinear): Fix coding style.
(android_ftruncate): New function.
* src/android.h: Update prototypes.  Replace ftruncate with
android_ftruncate when necessary.

* src/androidterm.c (handle_one_android_event): Pacify GCC.  Fix
touch screen tool bar bug.
* src/emacs.c (using_utf8): Fix compilation error.
* src/fileio.c (Ffile_system_info): Return Qnil when fsusage.o
is not built.
* src/filelock.c (BOOT_TIME_FILE): Fix definition for Android.
* src/frame.c (Fx_parse_geometry): Fix uninitialized variable
uses.
* src/keyboard.c (lispy_function_keys): Fix `back'.
* src/menu.c (x_popup_menu_1): Handle touch screen events.
(Fx_popup_menu): Document changes.

* src/sfnt.c (main): Improve tests.

* src/sfntfont-android.c (sfntfont_android_put_glyphs): Fix
minor problem.
(init_sfntfont_android): Check for
HAVE_DECL_ANDROID_GET_DEVICE_API_LEVEL.
* src/sfntfont.c (struct sfnt_font_desc): New fields `adstyle'
and `languages'.
(sfnt_parse_style): Append tokens to adstyle.
(sfnt_parse_languages): New function.
(sfnt_enum_font_1): Parse supported languages and adstyle.
(sfntfont_list_1): Handle new fields.
(sfntfont_text_extents): Fix uninitialized variable use.
(syms_of_sfntfont, mark_sfntfont): Adjust accordingly.

lisp/frame.el

@@ -2149,8 +2149,12 @@ frame's display)."
   "Return non-nil if popup menus are supported on DISPLAY.
 DISPLAY can be a display name, a frame, or nil (meaning the selected
 frame's display).
-Support for popup menus requires that the mouse be available."
-  (display-mouse-p display))
+Support for popup menus requires that a suitable pointing device
+be available."
+  ;; Android menus work fine with touch screens as well, and one must
+  ;; be present.
+  (or (eq (framep-on-display display) 'android)
+      (display-mouse-p display)))
 
 (defun display-graphic-p (&optional display)
   "Return non-nil if DISPLAY is a graphic display.