Changes

Summary

1. core: string: No need to NULL protect lwc_string_unref (details)
2. events: document event: No need to NULL protect lwc_string_unref (details)

Commit 2a88fa779c05d3eace62c1da7b638d07563cd29f by Michael Drake core: string: No need to NULL protect lwc_string_unref
	src/core/string.c
Commit cf129d2a0102afee144a315115b831e668c83cd1 by Michael Drake events: document event: No need to NULL protect lwc_string_unref
	src/events/document_event.c