[Merge] lp:~mvo/ubuntu/vivid/ubuntu-core-config/lp1460152-workaround into lp:ubuntu/ubuntu-core-config

[Jamie Strandboge]

>From the bug:
"FYI, the hash approach is slow for the normal case since we always have to perform an sum. Furthermore it doesn't take into account #include'd files that might also change (eg, apparmor is updated and has a different base abstraction). For the workaround, I guess it is ok since the slowdown will only be for a couple of profiles but I would have rather seen us unconditionally invalidating the cache when switching from a to b or vice versa."
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https://code.launchpad.net/~mvo/ubuntu/vivid/ubuntu-core-config/lp1460152-workaround/+merge/261179
Your team Ubuntu branches is requested to review the proposed merge of lp:~mvo/ubuntu/vivid/ubuntu-core-config/lp1460152-workaround into lp:ubuntu/ubuntu-core-config.