* java/org/gnu/emacs/EmacsOpenActivity.java (onCreate):
Don't check if URI is non-NULL, for instanceof checks this
also.

* java/org/gnu/emacs/EmacsSafThread.java (accessDocument1):
Don't check !writable twice.

* java/org/gnu/emacs/EmacsService.java (documentIdFromName):
Designate this function as public, since it is called
through JNI.

* java/org/gnu/emacs/EmacsWindow.java (onKeyDown): Disregard
KEYCODE_BACK events.
(onKeyUp): If the event is KEYCODE_BACK, deliver the disregarded
key press event, unless FLAG_CANCELED is set.

* java/org/gnu/emacs/EmacsService.java (externalStorageAvailable)
(requestStorageAccess23, requestStorageAccess30)
(requestStorageAccess): New functions.

* lisp/startup.el (fancy-startup-tail, normal-splash-screen):
Call android-win functions for inserting the new storage
permission notice.

* lisp/term/android-win.el
(android-display-storage-permission-popup)
(android-after-splash-screen): New functions.

* src/android.c (android_init_emacs_service): Link to new Java
functions.
(android_external_storage_available_p)
(android_request_storage_access): New functions.

* src/android.h: Update prototypes.

* src/androidfns.c (Fandroid_external_storage_available_p)
(Fandroid_request_storage_access): New functions.
(syms_of_androidfns): Register new subrs.

* doc/emacs/input.texi (Touchscreens): Address pinch gestures.

* doc/lispref/commands.texi (Touchscreen Events): Address touch
screen pinch events and the process by which they are produced.

* java/org/gnu/emacs/EmacsWindow.java (figureChange)
<ACTION_POINTER_DOWN>: Supply pointer index to getX and getY,
correcting a mistake where the first touch point's coordinate
was saved here in lieu of the pointer that was pressed's.

* lisp/touch-screen.el (touch-screen-current-tool): Revise doc
string.
(touch-screen-aux-tool): New variable.
(touch-screen-scroll-point-to-y, touch-screen-pinch): New
functions.
(global-map): Bind [touchscreen-pinch] to touch-screen-pinch.
(touch-screen-handle-point-update): Revise doc string; set new
tenth field of t-s-c-t to POINT relative to its window, without
regard to whether an event has been sent.
(touch-screen-distance, touch-screen-centrum): New functions.
(touch-screen-handle-aux-point-update): New function; generate
and send touchscreen-pinch if need be.
(touch-screen-handle-point-up): If an ancillary tool exists,
transfer the information there into touch-screen-current-tool
and clear t-s-a-t.
(touch-screen-handle-touch): Call t-s-a-p-u as is proper; set
t-s-a-t if a touchscreen-down event arrives and t-s-c-t is set.

* src/androidterm.c (handle_one_android_event): Properly save
the event's X and Y when a new touch point is registered.

* java/org/gnu/emacs/EmacsOpenActivity.java (onCreate):
EXTRA_EMAIL is an array rather than a string, so insert
its first element into an empty mailto URI.

* java/org/gnu/emacs/EmacsApplication.java (EmacsApplication)
<apkFileName>: New field.
(getApkFile): Move from EmacsService.java.
(findDumpFile): If the dump file is older than the APK, delete
it irrespective of whether the checksums agree.
(onCreate): Initialize apkFileName.

* java/org/gnu/emacs/EmacsService.java (onCreate): Use
EmacsApplication.apkFileName.

* src/android.c (android_on_low_memory): Correct arguments to
Fclear_image_cache.

* src/image.c (Fclear_image_cache): Check that animation_cache
is always a cons.

* java/org/gnu/emacs/EmacsNative.java (onLowMemory):

* java/org/gnu/emacs/EmacsService.java (onLowMemory): New
function.

* src/android.c (android_on_low_memory, onLowMemory): New
functions called when a VM caution is registered.  Clear
the image cache and run garbage collection.

* java/org/gnu/emacs/EmacsNative.java (shutDownEmacs):

* java/org/gnu/emacs/EmacsService.java (onDestroy): New
function.  When invoked, call shut_down_emacs and await its
completion.

* src/android.c (android_shut_down_emacs, shutDownEmacs): New
functions.

* java/org/gnu/emacs/EmacsNative.java (close): New declaration.

* java/org/gnu/emacs/EmacsSdk11Clipboard.java
(getClipboardData): Catch SecurityException and guarantee file
descriptors are closed even if exceptions arise.

* src/android.c (dup): Export another function.

* java/org/gnu/emacs/EmacsWindow.java (EmacsWindow)
<dndXPosition, dndYPosition>: New fields initialized to -1.
(onDragEvent): Remember the position of the previous event to
avoid sending duplicates.

* src/androidvfs.c (EMACS_PATH_MAX): New define.
(android_saf_tree_rename, android_saf_tree_opendir)
(android_name_file, android_fstatat, android_faccessat)
(android_fchmodat, android_readlinkat): Use EMACS_PATH_MAX where
SAF file names might be encountered.