Bug 914426. Don't try to dump DeprecatedTextureHost contents unless HTML tree dumping is enabled. Also, be lenient about null values and unknown formats. r=nrc

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extra : rebase_source : bc7aff0dacdea4a7c71bdb659774fd96a25fa529
Bug 920429. Fix busted boolean expression. r=mattwoodrow

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extra : rebase_source : fe144360e5f7b3399219d15cabc93c07a547c814