Add an OS.crash() method for testing system crash handler

This makes it possible to test the system's crash handler without
having to modify engine code or exploit an engine bug.

core/bind/core_bind.cpp

@@ -1182,6 +1182,10 @@ void _OS::alert(const String &p_alert, const String &p_title) {
 	OS::get_singleton()->alert(p_alert, p_title);
 }
 
+void _OS::crash(const String &p_message) {
+	CRASH_NOW_MSG(p_message);
+}
+
 bool _OS::request_permission(const String &p_name) {
 	return OS::get_singleton()->request_permission(p_name);
 }
@@ -1399,6 +1403,7 @@ void _OS::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_use_file_access_save_and_swap", "enabled"), &_OS::set_use_file_access_save_and_swap);
 
 	ClassDB::bind_method(D_METHOD("alert", "text", "title"), &_OS::alert, DEFVAL("Alert!"));
+	ClassDB::bind_method(D_METHOD("crash", "message"), &_OS::crash);
 
 	ClassDB::bind_method(D_METHOD("set_thread_name", "name"), &_OS::set_thread_name);
 	ClassDB::bind_method(D_METHOD("get_thread_caller_id"), &_OS::get_thread_caller_id);

core/bind/core_bind.h

@@ -356,6 +356,7 @@ class _OS : public Object {
 	String get_cache_dir() const;
 
 	void alert(const String &p_alert, const String &p_title = "ALERT!");
+	void crash(const String &p_message);
 
 	void set_screen_orientation(ScreenOrientation p_orientation);
 	ScreenOrientation get_screen_orientation() const;

doc/classes/OS.xml

@@ -43,6 +43,13 @@
 				[b]Note:[/b] This method is implemented on Linux, macOS and Windows.
 			</description>
 		</method>
+		<method name="crash">
+			<return type="void" />
+			<argument index="0" name="message" type="String" />
+			<description>
+				Crashes the engine (or the editor if called within a [code]tool[/code] script). This should [i]only[/i] be used for testing the system's crash handler, not for any other purpose. For general error reporting, use (in order of preference) [method @GDScript.assert], [method @GDScript.push_error] or [method alert]. See also [method kill].
+			</description>
+		</method>
 		<method name="delay_msec" qualifiers="const">
 			<return type="void" />
 			<argument index="0" name="msec" type="int" />
@@ -714,7 +721,7 @@
 			<return type="int" enum="Error" />
 			<argument index="0" name="pid" type="int" />
 			<description>
-				Kill (terminate) the process identified by the given process ID ([code]pid[/code]), e.g. the one returned by [method execute] in non-blocking mode.
+				Kill (terminate) the process identified by the given process ID ([code]pid[/code]), e.g. the one returned by [method execute] in non-blocking mode. See also [method crash].
 				[b]Note:[/b] This method can also be used to kill processes that were not spawned by the game.
 				[b]Note:[/b] This method is implemented on Android, iOS, Linux, macOS and Windows.
 			</description>