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/core_bind.cpp

@@ -207,6 +207,10 @@ 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);
+}
+
 String OS::get_executable_path() const {
 	return ::OS::get_singleton()->get_executable_path();
 }
@@ -542,6 +546,7 @@ void OS::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("close_midi_inputs"), &OS::close_midi_inputs);
 
 	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_low_processor_usage_mode", "enable"), &OS::set_low_processor_usage_mode);
 	ClassDB::bind_method(D_METHOD("is_in_low_processor_usage_mode"), &OS::is_in_low_processor_usage_mode);

core/core_bind.h

@@ -161,6 +161,7 @@ public:
 	int get_low_processor_usage_mode_sleep_usec() const;
 
 	void alert(const String &p_alert, const String &p_title = "ALERT!");
+	void crash(const String &p_message);
 
 	String get_executable_path() const;
 	int execute(const String &p_path, const Vector<String> &p_arguments, Array r_output = Array(), bool p_read_stderr = false);

doc/classes/OS.xml

@@ -31,6 +31,13 @@
 				[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 @GlobalScope.push_error] or [method alert]. See also [method kill].
+			</description>
+		</method>
 		<method name="create_instance">
 			<return type="int" />
 			<argument index="0" name="arguments" type="PackedStringArray" />
@@ -374,7 +381,7 @@
 			<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>