DBUS_METHOD_INVOCATION_HANDLED

The value returned by handlers of the signals generated by the `gdbus-codegen` tool to indicate that a method call has been handled by an implementation.

It is equal to true, but using this macro is sometimes more readable.

In code that needs to be backwards-compatible with older GLib, use true instead, often written like this:

	g_dbus_method_invocation_return_error (invocation, ...);
	return TRUE;		// handled