RFR: 8253407: Move max_pow2 from test to src

[Stefan Karlsson]

On Mon, 21 Sep 2020 09:46:59 GMT, Thomas Schatzl <tschatzl at openjdk.org> wrote:

>> Small refactoring to move test utility function over to src, so that it can be used in both places.
>> 
>> Patch summary:
>> - Moved the code
>> - Replaced duplicate code in round_power_of_2
>> - Adjusted to the surrounding powerOfTwo.hpp code and only accept integral types.
>> - Added small gtest. (On the fence whether it's worth it or not)
>
> Marked as reviewed by tschatzl (Reviewer).

Thanks for reviewing!

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PR: https://git.openjdk.java.net/jdk/pull/279