RFR: 8281631: HashMap copy constructor and putAll can over-allocate table [v9]

[XenoAmess]

On Tue, 15 Feb 2022 18:23:51 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 one additional commit since the last revision:
> 
>   9072610: HashMap copy constructor and putAll can over-allocate table

ConcurrentHashMap is a little complicated...
Would like to put it into another pr.
Let's focus on non-thread-safe Maps in this pr.

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