gtk-window-decorator leaks pixmaps

gtk-window-decorator leaks pixmaps and pixmap memory. This was addressed previously, but seems to have regressed.

To reproduce:
1) Open a terminal (gnome-terminal) and launch xrestop. Observe the number of pixmaps and amount of pixmap memory used by the gtk-window-decorator process
2) Open another terminal window. Observe that the number of pixmaps and amount of pixmap memory used by gtk-w-d goes up
3) Close the second terminal window. Observe the number of pixmaps / pixmap memory

Expected results:
Closing a window releases all resources attached to the window including pixmaps and pixmap memory

Actual results:
gtk-window-decorator retains one pixmap and 100KB+ from the old window.

This is reproducible on my system with other apps, not just terminal windows. After a few days' of usage, gtk-window-decorator has nearly 100MB of pixmap memory.

Sample xrestop output:

After step 1:
res-base Wins GCs Fnts Pxms Misc Pxm mem Other Total PID Identifier
2600000 167 66 1 140 316 15393K 13K 15407K 2439 gtk-window-dec

After step 2:
2600000 186 66 1 143 319 15639K 14K 15653K 2439 gtk-window-dec

After step 3:
2600000 167 66 1 141 317 15538K 13K 15552K 2439 gtk-window-dec

Notice the that between steps 1+2, 3 pixmaps were created. Only 2 were released (or all 3 were released and another was created?) between steps 2 and 3.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: compiz-gnome 1:0.9.9~daily13.03.01-0ubuntu1
ProcVersionSignature: Ubuntu 3.8.0-10.19-generic 3.8.2
Uname: Linux 3.8.0-10-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] Is a directory: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 310.14 Tue Oct 9 11:52:41 PDT 2012
 GCC version: gcc version 4.7.2 (Ubuntu/Linaro 4.7.2-22ubuntu2)
.proc.driver.nvidia.warnings.fbdev:
 Your system is not currently configured to drive a VGA console
 on the primary VGA device. The NVIDIA Linux graphics driver
 requires the use of a text-mode VGA console. Use of other console
 drivers including, but not limited to, vesafb, may result in
 corruption and stability problems, and is not supported.
.tmp.unity.support.test.0:

ApportVersion: 2.9-0ubuntu2
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist:
 GLib-GIO-Message: Using the 'memory' GSettings backend. Your settings will not be saved or shared with other applications.
 '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW:
 GLib-GIO-Message: Using the 'memory' GSettings backend. Your settings will not be saved or shared with other applications.
 true
Date: Wed Mar 6 11:35:43 2013
DistUpgraded: 2013-01-25 10:12:12,337 DEBUG enabling apt cron job
DistroCodename: raring
DistroVariant: ubuntu
GraphicsCard:
 NVIDIA Corporation G84 [GeForce 8600M GT] [10de:0407] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Apple Inc. Device [106b:00a0]
InstallationDate: Installed on 2010-09-17 (901 days ago)
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Beta amd64 (20100901.1)
MachineType: Apple Inc. MacBookPro3,1
MarkForUpload: True
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-10-generic root=UUID=4b3d81ed-fb5d-4946-97c0-ec537e1bfa3f ro quiet splash
SourcePackage: compiz
UpgradeStatus: Upgraded to raring on 2013-01-25 (40 days ago)
dmi.bios.date: 03/05/08
dmi.bios.vendor: Apple Inc.
dmi.bios.version: MBP31.88Z.0070.B07.0803051658
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: Mac-F4238BC8
dmi.board.vendor: Apple Inc.
dmi.board.version: PVT
dmi.chassis.asset.tag: Asset Tag#
dmi.chassis.type: 2
dmi.chassis.vendor: Apple Inc.
dmi.chassis.version: Mac-F4238BC8
dmi.modalias: dmi:bvnAppleInc.:bvrMBP31.88Z.0070.B07.0803051658:bd03/05/08:svnAppleInc.:pnMacBookPro3,1:pvr1.0:rvnAppleInc.:rnMac-F4238BC8:rvrPVT:cvnAppleInc.:ct2:cvrMac-F4238BC8:
dmi.product.name: MacBookPro3,1
dmi.product.version: 1.0
dmi.sys.vendor: Apple Inc.
version.compiz: compiz 1:0.9.9~daily13.03.01-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.42-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.0.2-0ubuntu1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.0.2-0ubuntu1
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.13.2-0ubuntu2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.1.0-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.21.3-0ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.6-0ubuntu3
xserver.bootTime: Tue Mar 5 17:39:03 2013
xserver.configfile: default
xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:

xserver.version: 2:1.13.2-0ubuntu2