RFR: 8302590: Add String.indexOf(int ch, int fromIndex, int toIndex)

[Raffaello Giulietti]

On Fri, 17 Feb 2023 21:21:30 GMT, ExE Boss <duke at openjdk.org> wrote:

>> Add an `indexOf()` variant allowing to specify both a lower and an upper bound on the search.
>
> Could we also get a similar overload for `String::lastIndexOf`?

@ExE-Boss See the second half [here](https://mail.openjdk.org/pipermail/core-libs-dev/2023-February/100391.html) for an explanation of why this is (currently) not part of this PR.

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PR: https://git.openjdk.org/jdk/pull/12600