Bug 849916 - Part 4: Don't rely on things still being around when we run PannerNode's dtor, use a weak pointer instead; r=roc

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extra : rebase_source : 8432bea9035761fcb52e77dfc474de8878fc4372
Bug 844872 - All addons and search engines present an option section even when the plugin does not have any options r=margaret
Bug 849211 - java.lang.NoSuchFieldException: bookmarkdefaults_favicon_support r=margaret
Bug 850377 - fix opt-only unused variable warnings in accessible/; r=tbsaunde
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
Bug 827347 - Allow force-downloading and installing of updates from about:firefox. r=snorp,blassey
Bug 849524 - Avoid reflowing when <input type=range>'s thumb position needs to be updated due to its value changing. r=dholbert