chore($http): Use copy to prevent modification of cached data

[kseamon]

chore($http): Use copy to prevent modification of cached data

Copy response data as it goes into and out of the cache.
This prevents modifications to cached data.

[mary-poppins]

Thanks for the PR!

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Thanks again for your help!

[petebacondarwin]

@kseamon - thanks for this PR. It makes a lot of sense. We will need you to sign the CLA and also we will need a unit test or two to demonstrate the feature before we can merge it.

[IgorMinar]

@petebacondarwin, karl is from google, working on DFA == no cla needed :)

[IgorMinar]

+1 for adding tests

[kseamon]

Actually, now that I look more closely at this to test it, I realize it is not needed. Everything going into that cache is a string, so copying does nothing.

[IgorMinar]

@kseamon I like how tests can better focus our thinking and reveal things that were not obvious before :)