Remove unused 'paused_' member from FakeServer class

BUG=none

Review-Url: https://codereview.chromium.org/2102003004
Cr-Commit-Position: refs/heads/master@{#402685}

ui/ozone/platform/wayland/fake_server.h

@@ -196,7 +196,6 @@ class FakeServer : public base::Thread, base::MessagePumpLibevent::Watcher {
 
   base::WaitableEvent pause_event_;
   base::WaitableEvent resume_event_;
-  bool paused_ = false;
 
   MockCompositor compositor_;
   MockSeat seat_;