Bug 981314: Relax block creation check for dead code in CheckIfCondition; r=luke

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extra : rebase_source : 87fce1b5514e3a65d3a8124e7e7d248ff3ea61ab
Bug 981325: Consider Float32 not to be a simple primitive; r=h4writer

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extra : rebase_source : 1a8d2f001f3bfa4acf60dfcc9fdbc901bd3b8345