bug 818675 implement new social share panel, r=felipe
Bug 857830: Part 1 - Ensure that ReadAheadFile's aOutFd is always set when provided. r=glandium

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extra : rebase_source : 8961f16a817a65325b356bd700b29665969f391c
Bug 857830: Part 2 - Adds readahead to read-only fopen calls in Hunspell. r=ehsan