Remove size from ResourceData

[natefinch]

We're not guaranteed to get a content-length from our get request, so we can't
guarantee we'll have anything to put in size.

This is half of a fix for https://bugs.launchpad.net/juju/+bug/1628786

[jujugui]

Test PASSed.
Refer to this link for build results (access rights to CI server needed):
http://ci.jujugui.org:8080//job/charmrepo/292/
Test PASSed.

[wallyworld]

It would be good to understand why content length is not always set. Can't we use it if set and ignore it if not? Why is it set sometimes and not others?

[mitechie]

+1 to @wallyworld as far as description of the problem and a link to the bug report on the charmstore that should be tracked/related to this issue.

[natefinch]

You can't trust content-length, evidently. It gets removed often in the case of gzipped responses. Since we also have the hash, which if it matches must mean the size matches as well.

[natefinch]

$$merge$$

[natefinch]

[jujugui]

Status: merge request accepted. Url: http://ci.jujugui.org:8080/job/charmrepo-merge