Bug 1067414 - Convert CubebUtils from a class of statics to a namespace.  r=jesup

--HG--
extra : rebase_source : 14c9e6709d5cc4fe978ee7ccc6d4f1988c09dd73
Bug 1067414 - Use atomic storage for sPreferredSampleRate.  r=jesup

--HG--
extra : rebase_source : 80913b082536bc29cfa8a20af4fd0f3277dd5a36
Bug 1065235 - Apply eviction to all decoders owned by TrackBuffer and make EvictData threshold apply per-TrackBuffer rather than per-decoder.  r=cajbir

--HG--
extra : rebase_source : f4ea425c9adeece7b37a4966131a1b566377add7
Bug 1065235 - Make the SourceBuffer eviction threshold a hidden pref.  r=cajbir

--HG--
extra : rebase_source : 7c22907cc774440f599cd972792d6d55a50151a2