[jdk8u] RFR: 8303828: [Solaris] Broken jdk8u build after JDK-8266391

[Severin Gehwolf]

On Thu, 9 Mar 2023 12:32:11 GMT, Adam Farley <afarley at openjdk.org> wrote:

> Because Solaris currently lacks this class, the build breaks when compiling Metrics.java. Inserting a dummy class to fix that.
> 
> This takes the same approach as [JDK-8303408](https://bugs.openjdk.org/browse/JDK-8303408), only on Solaris.
> 
> This change is being proposed directly to JDK8u because I'm not aware of Solaris platform support post-JDK8.
> 
> P.S. This PR is being created for jdk8u (as well as jdk8u-dev) as per this advice [here](https://github.com/openjdk/jdk8u-dev/pull/280#issuecomment-1460740821).

@adamfarley The bug is approved, feel free to `/integrate`

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PR: https://git.openjdk.org/jdk8u/pull/37