bug#19801: 25.0.50; eww uses incorrect base paragraph direction displaying Wikipedia "Languages"

[Eli Zaretskii]

To reproduce:

 emacs -Q
 M-x eww RET http://en.wikipedia.org/wiki/Ocelot RET
 C-s Languages

This scrolls to near the end of the page, where we are shown the list
of other languages in which this page is available.  Observe that the
list of languages is displayed as R2L text, flushed all the way to the
right edge of the window.

This happens because the first language in the list is Arabic, written
in the Arabic script, so Emacs decides that the following paragraph
has a R2L base direction.  And since there are no empty lines between
the languages, the whole list is then displayed as a single R2L
paragraph.

I presume that the page source specifies "dir=" somewhere, in which
case the solution is for eww to force bidi-paragraph-direction to the
corresponding value, or (if different blocks have different "dir="
attributes) to insert an LRM or RLM character at the beginning of each
such block of text.  See
http://www.w3.org/International/questions/qa-html-dir for more details
about this.

As the first stop-gap measure, I suggest to force the value of
bidi-paragraph-direction to 'left-to-right in the eww buffers, since
the vast majority of HTML pages are left to right.


In GNU Emacs 25.0.50.185 (i686-pc-mingw32)
 of 2015-02-07 on HOME-C4E4A596F7
Repository revision: cf498e5b9a73329edea0bdbf1bd8dfe06fdd75e2
Windowing system distributor `Microsoft Corp.', version 5.1.2600
Configured using:
 `configure --prefix=/d/usr --enable-checking=yes,glyphs 'CFLAGS=-O0
 -g3''

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB

Important settings:
  value of $LANG: ENU
  locale-coding-system: cp1255

Major mode: eww

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-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
  buffer-read-only: t
  line-number-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Contacting host: en.wikipedia.org:80
Mark set [2 times]
Mark saved where search started
mwheel-scroll: Beginning of buffer [3 times]
Contacting host: en.wikipedia.org:80
Mark set
Copied http://en.wikipedia.org/wiki/Carnivora
mwheel-scroll: End of buffer [3 times]

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message dired rfc822 mml mml-sec
mm-decode mm-bodies mm-encode mailabbrev gmm-utils mailheader sendmail
misearch multi-isearch shr-color color mule-util network-stream nsm
starttls url-http tls mail-parse rfc2231 rfc2047 rfc2045 ietf-drums
url-gw url-cache url-auth eww easymenu mm-url gnus gnus-ems nnheader
mail-utils wid-edit url-queue url url-proxy url-privacy url-expand
url-methods url-history url-cookie url-domsuf url-util url-parse
auth-source cl-macs eieio byte-opt gv bytecomp byte-compile cl-extra seq
cconv eieio-core cl-generic gnus-util mm-util help-fns mail-prsvr
password-cache url-vars mailcap shr dom cl-loaddefs cl-lib subr-x pcase
browse-url format-spec time-date tooltip eldoc electric uniquify
ediff-hook vc-hooks lisp-float-type mwheel dos-w32 ls-lisp disp-table
w32-win w32-vars 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 cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
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 make-network-process
w32notify w32 multi-tty emacs)

Memory information:
((conses 8 873154 68374)
 (symbols 32 23394 0)
 (miscs 32 60 194)
 (strings 16 66922 10505)
 (string-bytes 1 2843852)
 (vectors 8 35068)
 (vector-slots 4 843471 25486)
 (floats 8 284 260)
 (intervals 28 78317 1578)
 (buffers 516 14))