Refactor mount fakes

[codenrhoden]

What type of PR is this?
/kind cleanup

What this PR does / why we need it:
As part of the review for kubernetes/utils#100, it was requested to put all fakes in a testing subpackage.

After discussion, a different package structures was agreed on with @saad-ali and @thockin, see #81423 (review).

This patch moves fake.go to mount_fake.go, and follows to principle of
always returning a discrete type rather than an Interface. All callers
of "FakeMounter" are changed to instead use "NewFakeMounter()". The
FakeMounter "Log" struct member is changed to not be exported, and
instead only access through a new "GetLog()" method.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[codenrhoden]

OMG. Just realized, thanks to this test result that moving to a types package resolves our issue with the golinter! This means that the package now is all good from the linting perspective, negating all the issues raised in #81186. 🎉

[mattjmcnaughton]

Mind addressing the govet failures that are causing pull-kubernetes-verify to fail.

/test pull-kubernetes-bazel-test

Since this is such a big diff, I imagine we'll rely pretty heavily on CI for validation, so going to wait for that to be green before reviewing.

Also, to confirm - this pr changes no functionality correct? It just changes the modules of certain functionality?

[msau42]

@kubernetes/sig-storage-pr-reviews
/assign

[codenrhoden]

Mind addressing the govet failures that are causing pull-kubernetes-verify to fail.

yep, of course. Should be done now.

Also, to confirm - this pr changes no functionality correct? It just changes the modules of certain functionality?

That's the idea. The only real change is that in order for the FakeMounter to be independent in the testing package, it can't call into shared functions found in the top level mount package. There were two places that did this. They were simple pieces of re-used logic, and I merely copied them over. So - some logic is copied. That's probably worth pointing out. Doesn't change the "real" implementation, only the fake one.

[codenrhoden]

/retest

[codenrhoden]

/retest

[codenrhoden]

/retest

[codenrhoden]

/retest

[codenrhoden]

/test pull-kubernetes-e2e-gce-storage-slow

[codenrhoden]

/retest

[codenrhoden]

/retest

[jsafrane]

/lgtm
/approve

[codenrhoden]

/assign @Random-Liu @derekwaynecarr @tallclair
Any chance I can get a kubelet approver?

[dims]

/milestone v1.17

[derekwaynecarr]

the kubelet changes all look like straight forward refactors.

thanks!

/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: codenrhoden, derekwaynecarr, jsafrane, msau42

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Needs approval from an approver in each of these files:

• pkg/kubelet/OWNERS [derekwaynecarr]
• pkg/util/mount/OWNERS [jsafrane]
• pkg/volume/OWNERS [jsafrane,msau42]

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[fejta-bot]

/retest
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Review the full test history for this PR.

Silence the bot with an /lgtm cancel or /hold comment for consistent failures.

[vladimirvivien]

/lgtm

[codenrhoden]

Rebased after a new merge conflict in the same PR batch. Needed to add this line to use the new struct member added in a different PR: https://github.com/kubernetes/kubernetes/pull/81423/files#diff-b962320d780ac74dffce9da68eda4f4cR616