Fix the issue causing the screen to be black after resuming when in low processor mode.

This is done by forcing a redraw and buffers swap when resuming the app.

platform/android/java_godot_lib_jni.cpp

@@ -503,6 +503,8 @@ JNIEXPORT void JNICALL Java_org_godotengine_godot_GodotLib_onRendererResumed(JNI
 		return;
 	}
 
+	// We force redraw to ensure we render at least once when resuming the app.
+	Main::force_redraw();
 	if (os_android->get_main_loop()) {
 		os_android->get_main_loop()->notification(MainLoop::NOTIFICATION_APPLICATION_RESUMED);
 	}