Bug 884124 (part 4) - Add an ErrorObject class.  r=jwalden.

--HG--
extra : rebase_source : 9054445c5a435a1e49d1217247c5a32afef3826a
Bug 884124 (part 5) - Add a DateObject class.  r=jwalden.

--HG--
extra : rebase_source : bc39dcc8e2f8f2fcc71389a3ea199e264c445bc8
Bug 884124 (part 6) - Add an ArrayObject class.  r=jwalden.

--HG--
extra : rebase_source : 17a9703165cb665326ff94bc574450ba59ede7f7
Bug 884124 (part 7) - Move some methods from JSObject to ArrayObject.  r=jwalden.

--HG--
extra : rebase_source : bbe97ebfd1ef026f8a3ee21ce1b75f8b4ed40311
Bug 884124 (part 8) - Add a RegExpStaticObject class.  r=jwalden.

--HG--
extra : rebase_source : 9a0b0a59dc67cbab9ab1156607a984d303a850c3