Bug 1018355 - IPv6 tethering failure. r=chulee, a=1.4+

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extra : rebase_source : fa988e6b58460c0524f2ed1062e20c1cb16f09df
Bug 1018387 - Log the composition bounds in layer dumps. r=Cwiiis, a=2.0+

--HG--
extra : rebase_source : da5acc804eac7e889156bbcd96c241b1f043df73
Bug 1018387 - Add some logging for the tile drawing code. r=Cwiiis, a=2.0+

--HG--
extra : rebase_source : 6698a156e7b38061157fc256e8ae3446dc617a21
Bug 1018387 - Update various variables and comments to reflect the fact that the values are in layer pixels and not layout device pixels. r=Cwiiis, a=2.0+

--HG--
extra : rebase_source : da4179aedd9e2dce784d1e02a4b85876ecd43ff5
Bug 1018387 - Fix some calculations that were wrong because of confusion between LayoutDevice and Layer pixel spaces. r=botond, a=2.0+

--HG--
extra : rebase_source : 086376fe28abc870a93bd42a4b8ceceb3834d19b
Bug 1016738 - Back out for webrtc crashes. a=backout

--HG--
extra : rebase_source : 898a9c1a205e906575822ae7413b014e8b92c230