Merge pull request #45384 from caesarxuchao/copy-metrics-interanl

Automatic merge from submit-queue (batch tested with PRs 45382, 45384, 44781, 45333, 45543)

Copy internal types to metrics

Supersedes #45306. 

#45306 removed the internal types and suggested whoever needs the internal types should define their own copy, and use the code-gen tools to generated the conversion functions. Per offline discussion with @DirectXMan12, we wanted to go that direction but it's not clear where to put the internal types yet. Hence, as a temporary solution, we decided copy the referred client-go/pkg/api types into metrics api to avoid the dependency.

The commit "remove need of registry from custom_metrics/client.go" is similar to what I did to the fake client in an earlier PR. Let me know if you want to put the commit in another PR.

hack/update-codecgen.sh

@@ -51,6 +51,9 @@ generated_files=($(
         -o -wholename '*/codecgen-*-1234.generated.go' \
       \) -prune \
     \) -name '*.generated.go' | LC_ALL=C sort -r
+
+  find ./vendor/k8s.io/metrics/ \
+    -name '*.generated.go' | LC_ALL=C sort -r
 ))
 
 # We only work for deps within this prefix.