Automatic merge from submit-queue
Better kubectl run validations
Adds more validations to flags that must be mutually exclusive in `kubectl run`. For example, `--dry-run` must not be used with `--attach`, `--stdin` or `--tty`. Adds unit tests for these new validations and some previously existing ones.
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This is so that we can use NewAPIFactory() from cmd/set/*test.go
Up until now we would get a import loop error.
This commit also adds a basic unit test case for cmd/set/set_image.go
Combine the fields that will be used for content transformation
(content-type, codec, and group version) into a single struct in client,
and then pass that struct into the rest client and request. Set the
content-type when sending requests to the server, and accept the content
type as primary.
Will form the foundation for content-negotiation via the client.
The pending codec -> conversion split changes the signature of
Encode and Decode to be more complicated. Create a stub helper
with the exact semantics of today and do the simple mechanical
refactor here to reduce the cost of that change.