Bug 1022773 - Resolve hazard by switching Compile to MutableHandle, r=terrence, a=abillings

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extra : rebase_source : dd1e418e3f01c70ed6660cb4c5a00f79cb251e8d
Bug 1022773 - Return value rooting for content/, r=smaug, a=abillings

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extra : rebase_source : 3a604ae4fb83e0b3e876392213ef95d4924b8bf3
Bug 1022773 - Return value rooting for dom/, r=bz, a=abillings

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extra : rebase_source : 1760b74ba361af0010a2cac327ea9e2e3314cfc0
Bug 1022773 - Return value rooting for workers, r=bent, a=abillings

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extra : rebase_source : 38f3c3fa0d0c3a88df627b8b5e6dec2ec85146f9
Bug 1022773 - Return value rooting for JS engine, r=terrence, a=abillings

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extra : rebase_source : cf94c0e1e82bdac13800a65267ab1908d96d0df9
Bug 1022773 - Return value rooting for XPConnect, r=bholley, a=abillings

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extra : rebase_source : e6bb41c26718206ebe35b7c7b2443f1039d21c5a
Bug 1022773 - Return value rooting for SPS, r=ehsan, a=abillings

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extra : rebase_source : 9e3e84e97064a24ff4823b7b59c0e245bcb6f063