Bug 875169 - Fix crash when loading an HTMLTrackElement. r=bz

Previously we had been trying to load a DOMString that already has
a string buffer by using the DOMString::&operator. This causes a
MOZ_ASSERT error in DOMString. Solution is to add function overloads
to HTMLTrackElement's getters that just use nsString in the first place.
Bug 874808 - simpleDownload should accept string arguments and options. r=paolo
Bug 877626 - Port GTK2 to GTK3 - build config, gfx dir. r=karlt
Bug 879760 - Port GTK2 to GTK3 - browser dir. r=karlt
Bug 881608 - OdinMonkey: handle Type::Unknown when checking call args (r=bbouvier)

--HG--
extra : rebase_source : ca7bed61121e080743f5fc6dd35a7b36e1aa93dd
Bug 823978 - Rename JSOPTION_STRICT to JSOPTION_EXTRA_WARNINGS. r=Waldo

--HG--
extra : rebase_source : f5c0e9c743dadb0431eacef6b46b6e274264d3aa