Bug 1073252. Part 0: Add IsOpaque(SurfaceFormat). r=bas

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extra : rebase_source : 8aa2b0203db462573cd60046985d03a10a402fc9
Bug 1073252. Part 1: Track opaqueness of gralloc TextureClient/Host. r=nical

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extra : rebase_source : de08e7a128bad27250cae94386e8ffea5fa26d6d
Bug 1073252. Part 2: Store opaque flag in LayerRenderState. r=nical

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extra : rebase_source : a0fefe94dd52a6f365c34bffcd806e094c62d76e
Bug 1073252. Part 3: Use opaque flag from LayerRenderState in HWC. r=sotaro

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extra : rebase_source : b9e76ce39f1dc106c8ff214e7b7220f1255b8572
Bug 1073252. Part 4: Flip hasAlpha to isOpaque for consistency. r=mattwoodrow

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extra : rebase_source : a553b4c36feb555b23cbe140a05df09f0dc2656d
Bug 1073252. Part 5: Mark surfaces obtained from a buffer queue as opaque. r=sotaro

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extra : rebase_source : 9feef096e8d9856ac5e19ec7a87a8a3da08355c3