Bug 833542. Make scrollWidth/scrollHeight for overflow:visible match what they would be for overflow:hidden on the same element. r=mats

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extra : rebase_source : 42d1018cf48caf1eec4bc9251ec1cb3eee30001b
Bug 832788. Part 1: Make double->float conversions explicit in CanvasRenderingContext2D.cpp. r=jrmuizel

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extra : rebase_source : 626dc74eae93bb6a0d9bbb69db9440f251150169
Bug 832788. Part 2: AudioEventTimeline::IsValid needs to accept double. r=ehsan

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extra : rebase_source : 74c278d121419448b264ec3be4b8717bd99e15d1
Bug 832788. Part 3: AudioListener DopplerFactor/SpeedOfSound should take float per WebIDL. r=ehsan

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extra : rebase_source : d435b1678b09075cecf75e8da64364ec62964d00
Bug 832788. Part 4: PrimitiveConversions should avoid implicit narrowing casts to avoid compiler warnings; make them explicit. r=bzbarsky

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extra : rebase_source : 276f7834714ded347bd9d368258bc049f24787c4