bug#18333: 24.3.93; ImageMagick: ICO image in multiple sizes is not shown correctly

[YAMAMOTO Mitsuharu]

Steps to Reproduce:

1. Build Emacs with the ImageMagick support.

2. Download http://bits.wikimedia.org/favicon/wikipedia.ico and save
   it to "~/wikipedia.ico"

3. $ identify ~/wikipedia.ico

   The result would be:
    wikipedia.ico[0] ICO 16x16 16x16+0+0 32-bit sRGB 15.1KB 0.000u 0:00.000
    wikipedia.ico[1] ICO 32x32 32x32+0+0 32-bit sRGB 15.1KB 0.000u 0:00.000
    wikipedia.ico[2] ICO 48x48 48x48+0+0 32-bit sRGB 15.1KB 0.000u 0:00.000

   Note that the file contains multiple images in different sizes.

4. Invoke Emacs and evaluate the following expression in *scratch*:

    (let (sizes)
      (dotimes (i 3)
        (push (image-size
               (create-image "~/wikipedia.ico" 'imagemagick nil :index i) t)
              sizes))
      sizes)

   The expected result is ((16 . 16) (32 . 32) (48 . 48)) or its
   permutation, but the actual one is ((16 . 16) (16 . 16) (16 . 16)).

If you try 

  (dotimes (i 3)
    (insert-image (create-image "~/wikipedia.ico" 'imagemagick nil :index i)))

then you'll observe that larger images are clipped.

                                     YAMAMOTO Mitsuharu
                                mituharu@math.s.chiba-u.ac.jp

In GNU Emacs 24.3.93.1 (x86_64-apple-darwin10.8.0, GTK+ Version 3.12.2)
 of 2014-08-27 on yamamoto-mitsuharu-no-iMac.local
Windowing system distributor `The X.Org Foundation', version 11.0.10402000
Configured using:
 `configure CPPFLAGS=-I/opt/local/include LDFLAGS=-L/opt/local/lib'