make error: Plugin.hpp:37:9: error: ‘GdkSeat’ does not name a type

[diogofd8]

Making all in src
make[1]: Entering directory '/home/efacec/docklike-plugin/src'
  CXX      libdocklike_la-Hotkeys.lo
In file included from GroupWindow.hpp:20:0,
                 from Dock.hpp:16,
                 from Settings.hpp:17,
                 from Hotkeys.hpp:19,
                 from Hotkeys.cpp:7:
Plugin.hpp:37:9: error: ‘GdkSeat’ does not name a type
  extern GdkSeat* seat;
         ^
In file included from Dock.hpp:16:0,
                 from Settings.hpp:17,
                 from Hotkeys.hpp:19,
                 from Hotkeys.cpp:7:
GroupWindow.hpp:50:2: error: ‘GdkMonitor’ does not name a type
  GdkMonitor* mMonitor = NULL;
  ^
Makefile:619: recipe for target 'libdocklike_la-Hotkeys.lo' failed

Hello, I'm trying to compile the plugin for Ubuntu 16.04, is it too old of a version to not work by downgrading the dev packages of all the dependencies? Unfortunately this is a work machine so I cannot upgrade, is there any workaround?