Take host state into account when sending suppressed notifications

Checkable::FireSuppressedNotifications() compares the time of the current
checkable with the last recovery time of parents to avoid notification right
after a parent recovered and before the current checkable was checked.

This commit makes this check also include to host if the checkable is a
service.  This makes the behavior consistent with the documentation that states
there is an implicit dependency on the host (which isn't realized as implicitly
generating a Dependency object unfortunately).

lib/icinga/checkable-notification.cpp

@@ -155,6 +155,17 @@ void Checkable::FireSuppressedNotifications()
 			}
 
 			auto threshold (cr->GetExecutionStart());
+			Host::Ptr host;
+			Service::Ptr service;
+			tie(host, service) = GetHostService(this);
+
+			if (service) {
+				ObjectLock oLock (host);
+
+				if (!host->GetProblem() && host->GetLastStateChange() >= threshold) {
+					return true;
+				}
+			}
 
 			for (auto& dep : GetDependencies()) {
 				auto parent (dep->GetParent());