Hidden Unity toolbar still receives mouse clicks when fullscreen applications are unfocused in multihead environments

[Benjamin Xiao]

This is a follow up to bug #748539 which fixed the issue where the Unity toolbar was still displaying on top of fullscreen applications if they were unfocused. It is correctly hidden, but it seems like the toolbar still receives mouse clicks. When I click in the region where the Unity toolbar should be if it wasn't hidden, instead of clicking in the fullscreen app, it registers as a mouse click on the toolbar.

For example:

1.) Open up Chrome and load any stream on Twitch.tv. Put Chrome on the first monitor and fullscreen it.
2.) Focus on any application on the second monitor.
3.) Without changing focus, move mouse cursor back into first monitor and try to click the Play/Pause button in Twitch. Instead of playing or pausing, it launches the Trash.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: unity 7.2.2+14.04.20140714-0ubuntu1.1
ProcVersionSignature: Ubuntu 3.13.0-35.62-generic 3.13.11.6
Uname: Linux 3.13.0-35-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu3.3
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CurrentDesktop: Unity
Date: Sat Aug 30 02:53:38 2014
InstallationDate: Installed on 2014-04-18 (134 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: No upgrade log present (probably fresh install)