bug 824396 - implement mach buildsymbols. r=gps

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extra : rebase_source : 3c0a4ebaa2d5537368e40e4dbac2fcf784ad41be
bug 751673 - fix Windows assertion stacks. r=dbaron

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extra : rebase_source : b74882bb3914afaa44341088b9f737c909e88f65
Bug 848401: switch from ReentrantMonitors and PR_Lock/Condvar to Monitor.  Fix {picture:true} for desktop r=khuey,dao