Bug 940178 - Build cairo in unified mode. r=ehsan

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extra : rebase_source : b24a1e1f1384c78f0d09d84c573d11e57024b43a
Bug 940416 - Build gfx/harfbuzz in unified mode. r=ehsan

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extra : rebase_source : 2d656203217681d0d1518dbb6e0f680f63d3dd92
Bug 937119 - Fix stereo setting errors on Android/OpenSLES. r=jesup
Bug 937119 - Increase default Android audio buffers to 40ms. r=jesup