Bug 899420 - Re-enable test_seek, test_buffered, test_bug493187, test_playback_rate, test_bug465498, test_played on Linux r=cpearce
Bug 886181 - Pref on gstreamer backend r=cpearce
Bug 913965 - Don't use build-dep for installing dependencies; install modern Mercurial on Ubuntu; r=glandium

DONTBUILD (NPOTB)
Bug 906371 - Use off thread JS parsing when loading async scripts, r=bz,billm.
Backout changeset 237c32279481 (bug 914482) for bustage
Bug 912514 - Don't release nsIURIs off-main-thread. r=jdm
Bug 791916 - Make label tag a label accessible regardless of frame type. r=surkov
bug 887819 - Investigate using the tiled layers backend, turn on tiles for b2g r=gal,benwa

--HG--
extra : rebase_source : c288e8145fd4409b0231f1c83eed0ba8ce60c136