bug 929093 - vcs-sync: remove bare_checkout, add denyDeletes, nuke failed clones. r=hwine

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extra : rebase_source : 896f9087f2f1ad630ae7e8a3ec433edfe741843e
Bug 933431 - Android mozharness config needs to specify -j for jit-tests; r=aki

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extra : transplant_source : 7j%DF%7D%03%E9%9AK%8D4%D51%20%DD%7EQ%00_%3D%E9