RFR: 8264137: Suppress deprecation and removal warnings of internal methods

[Kevin Rushforth]

On Mon, 21 Jun 2021 11:24:39 GMT, Ajit Ghaisas <aghaisas at openjdk.org> wrote:

> This PR suppresses -PLINT="removal" warnings and fixes -PLINT="deprecation" warnings. I have created separate commits for each type of warnings for the ease of review.
> 
> `gradle --info -PLINT="deprecation,removal"` -- results in warnings during build without this PR and results in no warnings with this PR.

Looks good.

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Marked as reviewed by kcr (Lead).

PR: https://git.openjdk.java.net/jfx/pull/538