Bug 1024148 - Part 1: Merge nsDisplayOpacity items together. r=mattwoodrow

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extra : rebase_source : f461cb97357c854db22122b40777358a17f736ec
Bug 1024148 - Part 2: Merge nsDisplayOpacity into nsDisplayBackgroundColor. r=mattwoodrow

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extra : rebase_source : c48cc799414ff83b74caff8df5503a743dbf74b1
Bug 1025704 - Add --video flag to merge-profiles.py. r=ehsan