Bug#770556: libgtk-3-0: icon-shadow for SVG icons doesn't get scaled properly

[Margarita Manterola]

Package: libgtk-3-0
Version: 3.14.4-2
Severity: important

Dear Maintainer,

This problem is showing up in cinnamon, although I expect it also shows up in
any other programs that use GTK and make use of the icon-shadow property.

This is the bug report for cinnamon:
https://github.com/linuxmint/Cinnamon/issues/3577

The problem only happens with SVG icons, and what happens is that the
icon-shadow is not scaled to the same scaling that the icon is.

The workaround for cinnamon is to not use the icon-shadow property, but the
right fix would be to make the icon-shadow scale correctly to the size of the
icon.

I've reproduced this both in testing and unstable.

-- System Information:
Debian Release: jessie/sid
  APT prefers testing
Architecture: amd64 (x86_64)

Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=es_AR.UTF-8, LC_CTYPE=es_AR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages libgtk-3-0 depends on:
ii  libatk-bridge2.0-0   2.14.0-2
ii  libatk1.0-0          2.14.0-1
ii  libc6                2.19-13
ii  libcairo-gobject2    1.14.0-2.1
ii  libcairo2            1.14.0-2.1
ii  libcolord2           1.2.1-1+b1
ii  libcups2             1.7.5-7
ii  libfontconfig1       2.11.0-6.1
ii  libfreetype6         2.5.2-2
ii  libgdk-pixbuf2.0-0   2.31.1-2+b1
ii  libglib2.0-0         2.42.0-2
ii  libgtk-3-common      3.14.4-2
ii  libjson-glib-1.0-0   1.0.2-1
ii  libpango-1.0-0       1.36.8-2
ii  libpangocairo-1.0-0  1.36.8-2
ii  libpangoft2-1.0-0    1.36.8-2
ii  librest-0.7-0        0.7.92-2
ii  libsoup2.4-1         2.48.0-1
ii  libwayland-client0   1.6.0-2
ii  libwayland-cursor0   1.6.0-2
ii  libx11-6             2:1.6.2-3
ii  libxcomposite1       1:0.4.4-1
ii  libxcursor1          1:1.1.14-1+b1
ii  libxdamage1          1:1.1.4-2
ii  libxext6             2:1.3.3-1
ii  libxfixes3           1:5.0.1-2+b1
ii  libxi6               2:1.7.4-1+b1
ii  libxinerama1         2:1.1.3-1+b1
ii  libxkbcommon0        0.4.3-2
ii  libxml2              2.9.1+dfsg1-4
ii  libxrandr2           2:1.4.2-1+b1
ii  multiarch-support    2.19-13
ii  shared-mime-info     1.3-1

Versions of packages libgtk-3-0 recommends:
ii  hicolor-icon-theme  0.13-1
ii  libgtk-3-bin        3.14.4-2

Versions of packages libgtk-3-0 suggests:
ii  gvfs             1.22.1-1
ii  librsvg2-common  2.40.5-1