Bug 837950 - Import test402 source files.  r=jwalden

--HG--
extra : rebase_source : 7de0eedbac0476fcc2a91fa8cce60a7437e56d2d
Bug 858677 - Make the internal deletion operations not take a strictness argument and a Value*, but rather take a JSBool* -- and let callers handle the property-couldn't-be-deleted (but no error occurred) case.  r=jorendorff
Bug 858677 - Fix up code not built by SpiderMonkey to use the newly-changed deletion signatures.  r=bholley, r=billm