bug#24512: 25.1; ends of buffer scroll causes distracting large yellow error

[Jeff Hodges <jeff@somethingsimilar.com>]

In 25.1, using the mouse wheel trying to scroll to the bottom or top of a
buffer will throw up a large, distracting yellow warning symbol in the
middle of a buffer. (It's a yellow triangle with a white exclamation
mark.) This was not occurring in 24.x.



In GNU Emacs 25.1.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version 10.9.5 (Build 13F1911))
 of 2016-09-17 built on builder10-9.porkrind.org
Windowing system distributor 'Apple', version 10.3.1504
Configured using:
 'configure --with-ns '--enable-locallisppath=/Library/Application
 Support/Emacs/${version}/site-lisp:/Library/Application
 Support/Emacs/site-lisp''

Configured features:
NOTIFY ACL GNUTLS LIBXML2 ZLIB TOOLKIT_SCROLL_BARS NS

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Perl

Minor modes in effect:
  diff-auto-refine-mode: t
  magit-auto-revert-mode: t
  global-git-commit-mode: t
  async-bytecomp-package-mode: t
  shell-dirtrack-mode: t
  global-auto-complete-mode: t
  auto-complete-mode: t
  show-paren-mode: t
  save-place-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
mwheel-scroll: Beginning of buffer [2 times]
<wheel-left> is undefined
<double-wheel-left> is undefined
<triple-wheel-left> is undefined [12 times]
<wheel-left> is undefined
mwheel-scroll: Beginning of buffer [6 times]
<nil> <wheel-up> is undefined
mwheel-scroll: Beginning of buffer [20 times]
mwheel-scroll: End of buffer [9 times]
Making completion list...

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug perl-mode view pulse eieio-opt speedbar
sb-image ezimage dframe find-func python vc vc-dispatcher imenu vc-git
misearch multi-isearch cc-langs cc-mode cc-fonts cc-guess cc-menus
cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs ht s noutline
outline ediff-merg ediff-wind ediff-diff ediff-mult ediff-help
ediff-init ediff-util ediff magit-blame magit-stash magit-bisect
magit-remote magit-commit epa magit-sequence magit dired-x magit-apply
magit-wip magit-log magit-diff smerge-mode diff-mode magit-core
magit-autorevert autorevert filenotify magit-process magit-popup
magit-mode magit-git crm magit-section magit-utils git-commit recentf
tree-widget wid-edit with-editor term ehelp esh-var esh-io esh-cmd
esh-opt esh-ext esh-proc esh-arg esh-groups eshell esh-module esh-mode
esh-util async-bytecomp tramp-sh tramp tramp-compat tramp-loaddefs
trampver shell pcomplete log-edit pcvs-util add-log dash hippie-exp ewoc
rx sh-script smie executable message format-spec rfc822 mml mml-sec epg
mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils
mailheader smtpmail sendmail rfc2047 rfc2045 ietf-drums mail-utils
dired-aux dired async warnings flymake server auto-complete-config
go-autocomplete auto-complete popup python-mode-config
dockerfile-mode-config sh-mode-config js-mode-config go-mode-config
go-guru easy-mmode cl json map go-rename go-mode url url-proxy
url-privacy url-expand url-methods url-history url-cookie url-domsuf
url-util mailcap find-file ffap thingatpt url-parse auth-source
gnus-util mm-util help-fns mail-prsvr password-cache url-vars etags xref
cl-seq project eieio eieio-core cl-macs compile comint ansi-color ring
go-mode-autoloads web-mode-config web-mode advice derived disp-table
css-mode-config markdown-mode-config sudo-edit rename-file-and-buffer
font-config font_config exec-path-from-shell key-bindings
better-defaults paren edmacro kmacro saveplace ido install finder-inf
info package epg-config seq byte-opt gv bytecomp byte-compile cl-extra
help-mode easymenu cconv cl-loaddefs pcase cl-lib time-date mule-util
tooltip eldoc electric uniquify ediff-hook vc-hooks lisp-float-type
mwheel ns-win ucs-normalize term/common-win tool-bar dnd fontset image
regexp-opt fringe tabulated-list newcomment elisp-mode lisp-mode
prog-mode register page menu-bar rfn-eshadow timer select scroll-bar
mouse jit-lock font-lock syntax facemenu font-core frame cl-generic cham
georgian utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao
korean japanese eucjp-ms cp51932 hebrew greek romanian slovak czech
european ethiopic indian cyrillic chinese charscript case-table epa-hook
jka-cmpr-hook help simple abbrev minibuffer cl-preloaded nadvice
loaddefs button faces cus-face macroexp files text-properties overlay
sha1 md5 base64 format env code-pages mule custom widget
hashtable-print-readable backquote kqueue cocoa ns multi-tty
make-network-process emacs)

Memory information:
((conses 16 697528 72112)
 (symbols 48 44273 1)
 (miscs 40 381 2115)
 (strings 32 142148 5660)
 (string-bytes 1 3121122)
 (vectors 16 58824)
 (vector-slots 8 973142 25729)
 (floats 8 434 1006)
 (intervals 56 12257 848)
 (buffers 976 47))