Make recursive nature of iteration not fail.

main/main.cpp

@@ -1789,9 +1789,9 @@ uint64_t Main::target_ticks = 0;
 uint32_t Main::frames = 0;
 uint32_t Main::frame = 0;
 bool Main::force_redraw_requested = false;
-bool Main::iterating = false;
+int Main::iterating = 0;
 bool Main::is_iterating() {
-	return iterating;
+	return iterating > 0;
 }
 
 // For performance metrics
@@ -1803,7 +1803,7 @@ bool Main::iteration() {
 	//for now do not error on this
 	//ERR_FAIL_COND_V(iterating, false);
 
-	iterating = true;
+	iterating++;
 
 	uint64_t ticks = OS::get_singleton()->get_ticks_usec();
 	Engine::get_singleton()->_frame_ticks = ticks;
@@ -1932,7 +1932,7 @@ bool Main::iteration() {
 		frames = 0;
 	}
 
-	iterating = false;
+	iterating--;
 
 	if (fixed_fps != -1)
 		return exit;

main/main.h

@@ -47,7 +47,7 @@ class Main {
 	static uint32_t frames;
 	static uint32_t frame;
 	static bool force_redraw_requested;
-	static bool iterating;
+	static int iterating;
 
 public:
 	static bool is_project_manager();