event/*Monitor: add method GetEventLoop()

src/event/DeferredMonitor.hxx

@@ -44,6 +44,10 @@ public:
 		Cancel();
 	}
 
+	EventLoop &GetEventLoop() {
+		return loop;
+	}
+
 	void Schedule();
 	void Cancel();
 

src/event/MultiSocketMonitor.hxx

@@ -63,7 +63,10 @@ public:
 	MultiSocketMonitor(EventLoop &_loop);
 	~MultiSocketMonitor();
 
-public:
+	EventLoop &GetEventLoop() {
+		return loop;
+	}
+
 	gcc_pure
 	gint64 GetTime() const {
 		return g_source_get_time(&source->base);

src/event/SocketMonitor.hxx

@@ -66,6 +66,10 @@ public:
 
 	~SocketMonitor();
 
+	EventLoop &GetEventLoop() {
+		return loop;
+	}
+
 	bool IsDefined() const {
 		return fd >= 0;
 	}

src/event/TimeoutMonitor.hxx

@@ -38,6 +38,10 @@ public:
 		Cancel();
 	}
 
+	EventLoop &GetEventLoop() {
+		return loop;
+	}
+
 	bool IsActive() const {
 		return source != nullptr;
 	}