Bug 871179 - Fix rooting hazards in netwerk's Dashboard.cpp; r=till

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extra : rebase_source : b20df14656861f5cef10d1200580f23598632163
Bug 871181 - Fix rooting hazards in ObjectWrapperChild.cpp; r=till

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extra : rebase_source : 6666339f5970fe0a65b46868e1155c1af74f27d2
Bug 871182 - Fix rooting hazards in ObjectWrapperParent.cpp; r=till

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extra : rebase_source : 374a30e6001d8a1935f7cf57e8bf8a7cf2e03b05