backout of
https://hg.mozilla.org/integration/mozilla-inbound/rev/93501fc853ed
Bug 885784; not intended to push, old bug

--HG--
extra : rebase_source : 3ff8955be64870195163d1368ff136619f0e8c93
extra : amend_source : 6e734c23067299d711bb5d477cc3e5bca369aaae
Bug 898881 - Enable OpenSearch auto discovery for private windows; r=jdm
Bug 889682 - Eagerly check for remembered set membership before buffering; r=billm

--HG--
extra : rebase_source : 83da73e4ee40f2185b63b214b6710b9146109ff1
Bug 878156 - Mark all startup tabs as external. r=mfinkle
Bug 895728 part 1.  Introduce "boolean" and "numeric" types, since those will be treated differently for purposes of distinguishability and overload resolution.  r=khuey
Bug 895728 part 2.  Make booleans, numerics, and strings/enums all be distinguishable from each other.  r=khuey
Bug 895728 part 3.  Fix overload resolution to work with the new boolean/numeric/string setup.  r=khuey
Bug 895728 part 4.  Fix unions to work with the new boolean/numeric/string setup.  r=khuey
Bug 899547 - add needs-focus to editor reftests; r=ehsan