"Ubuntu Unity Plugin Switcher" does not respect "Skip pager" from "Window Rule"

[André]

Defining a "Skip taskbar" or "Skip pager" rule in "Window Rules" plugin does not reflect in the Ubuntu Unity Plugin Switcher, as the window still appears in the switcher.

This integration is expected, as other plugins respect this rule. Among other are:
- Scale - with "Skip pager" rule ;
- Application Switcher - with "Skip taskbar" rule;
- Static Application Switcher - with "Skip taskbar" rule.

How to reproduce:
1. Enable "Window Rules" plugin
2. Write: "class=Firefox" in the "Skip taskbar" rule
3. Open Firefox browser
4. Press "Alt+Tab" to see that Firefox still appears in Switcher
5. Try "Scale" plugin or any other of the mentioned above to see that Firefox window is ignored

Although this might not be relevant for firefox (the example above), it might be for other use cases, such as embedded windows, "Hangouts" app in google chrome, etc..

Technical info:
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Description: Ubuntu 14.04 LTS
Release: 14.04

compiz:
  Installed: 1:0.9.11.1+14.04.20140701-0ubuntu1