Bug 918634 - swapFrameLoader not implemented for e10s r=nical
Allow layers to change layermanager if using LayerManagerComposite.

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extra : rebase_source : f24fde110f91fff7e2ceb3ddcd4549077a15f3c6
Bug 918634 - swapFrameLoader not implemented for e10s.  Frameloader impl. r=smaug

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extra : rebase_source : 01867c6208df8213b04469404dc6c1f768f8c025