Bug 1092260. Block D3D11 layers on AMD hardware that delays by a frame. r=bas

It seems that some AMD drivers delay D3D11 output by a frame.
This shows up in other apps like Chrome:
https://code.google.com/p/chromium/issues/detail?id=402134

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extra : rebase_source : 6c2137edea70a655c0838d5a5b7d71e04cec74b3