RFR: 8281631: HashMap copy constructor and putAll can over-allocate table [v33]

[XenoAmess]

On Fri, 11 Mar 2022 15:56:26 GMT, XenoAmess <duke at openjdk.java.net> wrote:

>> 8281631: HashMap copy constructor and putAll can over-allocate table
>
> XenoAmess has updated the pull request incrementally with two additional commits since the last revision:
> 
>  - change KeyStructure to String
>  - fix test

![image](https://user-images.githubusercontent.com/17455337/157909872-8702460d-6945-435a-b866-02394b0fc220.png)
seems ci fails for network failure.

@stuart-marks I refine the tests using String to replace KeyStructure. Please have a look. thanks!

-------------

PR: https://git.openjdk.java.net/jdk/pull/7431