Bug 739757 - Back it out fully this time on a CLOSED TREE.
Backed out changeset f856bcb5097f (bug 689256) for xpcshell orange on a CLOSED TREE.
Bug 848031; r=gavin

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extra : rebase_source : 0ffb1e5904f3234d908c6441c13163b47b2ae3e7
Bug 810151: readahead for ordered jar files r=taras

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extra : rebase_source : dd7984ff2dd7a57e77b8c5c74ab82ad5d033a772