bug#11554: 24.0.97; nxml-auto-insert-xml-declaration-flag + zipped xml files

[Jambunathan K]

1. (setq nxml-auto-insert-xml-declaration-flag t)
2. Visit the attached test.zip

      M Filemode      Length  Date         Time      File
      - ----------  --------  -----------  --------  ----------
        drwx------         0  25-May-2012  00:29:06  test/
        -rwx------        40  25-May-2012  00:29:06  test/a.xml
      - ----------  --------  -----------  --------  ----------
                    40                         2 files
3. Visit a.xml.  Note the multiple XML declarations.

      <?xml version="1.0" encoding="utf-8"?>
      <?xml version="1.0" encoding="utf-8"?>

   The original file has just a single XML declaration.  The second
   declaration is the gratuitous declaration added due to (1).

   Why is nxml mode tampering with an existing XML file?

4. The problem surfaces with XML files in a ZIP archive (for example ODT
   files) and not with standalone XML files.

In GNU Emacs 24.0.97.1 (i386-mingw-nt5.1.2600)
 of 2012-05-17 on MARVIN
Windowing system distributor `Microsoft Corp.', version 5.1.2600
Configured using:
 `configure --with-gcc (4.6) --no-opt --enable-checking --cflags
 -ID:/devel/emacs/libs/libXpm-3.5.8/include
 -ID:/devel/emacs/libs/libXpm-3.5.8/src
 -ID:/devel/emacs/libs/libpng-dev_1.4.3-1/include
 -ID:/devel/emacs/libs/zlib-dev_1.2.5-2/include
 -ID:/devel/emacs/libs/giflib-4.1.4-1/include
 -ID:/devel/emacs/libs/jpeg-6b-4/include
 -ID:/devel/emacs/libs/tiff-3.8.2-1/include
 -ID:/devel/emacs/libs/gnutls-3.0.9/include'

test.zip
Description: Zip archive