Apt inconsistent in reporting download progress

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I'm actually changing the bug status to Confirmed

Status changed after discussions on the #ubuntu-bugs channel agreed that this is a bug, and not a wishlist.

marking as triaged, low importance.

I tried to fix this bug and it's not really a big bug, because there must be changed only one line.

This is my first bug I'm fixing for Ubuntu, so please be patient :)
The debdiff I've create is quite long, and I trimmed it a little bit (*_short.debdiff).

I don't know how the process goes on, maybe someone could leave a comment. Great :)

This bug was fixed in the package apt - 0.7.25.3ubuntu1

---------------
apt (0.7.25.3ubuntu1) lucid; urgency=low

  [ Michael Vogt ]
  * merged with the debian-sid branch

  [ Ivan Masár ]
  * Slovak translation update. Closes: #568294

apt (0.7.25.3) unstable; urgency=low

  [ Christian Perrier ]
  * Italian translation update. Closes: #567532

  [ David Kalnischkies ]
  * apt-pkg/contrib/macros.h:
    - install the header system.h with a new name to be able to use
      it in other headers (Closes: #567662)
  * cmdline/acqprogress.cc:
    - Set Mode to Medium so that the correct prefix is used.
      Thanks Stefan Haller for the patch! (Closes: #567304 LP: #275243)
  * ftparchive/writer.cc:
    - generate sha1 and sha256 checksums for dsc (Closes: #567343)
  * cmdline/apt-get.cc:
    - don't mark as manually if in download only (Closes: #468180)

apt (0.7.25.2) unstable; urgency=low

  [ Michael Vogt ]
  * apt-pkg/contrib/cdromutl.cc:
    - fix UnmountCdrom() fails, give it a bit more time and try
      the umount again
  * apt-pkg/cdrom.cc:
    - fix crash in pkgUdevCdromDevices
  * methods/cdrom.cc:
    - fixes in multi cdrom setup code (closes: #549312)
    - add new "Acquire::cdrom::AutoDetect" config that enables/disables
      the dlopen of libudev for automatic cdrom detection. Off by default
      currently, feedback/testing welcome
  * cmdline/apt-cdrom.cc:
    - add new --auto-detect option that uses libudev to figure out
      the cdrom/mount-point
  * cmdline/apt-mark:
    - merge fix from Gene Cash that supports markauto for
      packages that are not in the extended_states file yet
      (closes: #534920)
  * ftparchive/writer.{cc,h}:
    - merge crash fix for apt-ftparchive on hurd, thanks to
      Samuel Thibault for the patch (closes: #566664)

  [ David Kalnischkies ]
  * apt-pkg/contrib/fileutl.cc:
    - Fix the newly introduced method GetListOfFilesInDir to not
      accept every file if no extension is enforced
      (= restore old behaviour). (Closes: #565213)
  * apt-pkg/policy.cc:
    - accept also partfiles with "pref" file extension as valid
  * apt-pkg/contrib/configuration.cc:
    - accept also partfiles with "conf" file extension as valid
  * doc/apt.conf.5.xml:
    - reorder description and split out syntax
    - add partfile name convention (Closes: #558348)
  * doc/apt_preferences.conf.5.xml:
    - describe partfile name convention also here
  * apt-pkg/deb/dpkgpm.cc:
    - don't segfault if term.log file can't be opened.
      Thanks Sam Brightman for the patch! (Closes: #475770)
  * doc/*:
    - replace the per language addendum with a global addendum
    - add a explanation why translations include (maybe) english
      parts to the new global addendum (Closes: #561636)
  * apt-pkg/contrib/strutl.cc:
    - fix malloc asseration fail with ja_JP.eucJP locale in
      apt-cache search. Thanks Kusanagi Kouichi! (Closes: #548884)

  [ Christian Perrier ]
  * French translation update

apt (0.7.25.1) unstable; urgency=low

  [ Christian Perrier ]
  * French manpage translation update
  * Russian translation update by Yuri Kozlov
    Closes: #564171

  [Chris Leick]
  * spot & fix various typos in all manpages
...