DeferredDiscoveryRESTMapper won't automatically `Reset` itself before its
initial use, since actually trying to construct the delegate will error
out before it gets a chance to `Reset` itself. Ergo, we have to
manually call `Reset` before use.
note that we don't change the behaviour of kubectl.
For example it won't scale new resources. That's the end goal.
The first step is to retrofit existing code to use the generic scaler.
Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.
Add performance test phase timing export.
**What this PR does / why we need it**:
First step totwards allowing us to get a quick overview of test length
via perf-dash.k8s.io.
**Release note**:
```release-note
NONE
```
@kubernetes/sig-scalability-feature-requests
