RFR: 8278595: Provide more information when a pipeline can't be used

[danielpeintner]

On Mon, 13 Dec 2021 11:00:02 GMT, Johan Vos <jvos at openjdk.org> wrote:

> This PR provides at least some basic information when a pipeline can't be used. 
> There are a number of reasons why a candidate pipeline can't be used, and this PR makes it clear at which point the pipeline fails. 
> 
> The changes are only applied in case `prism.verbose` is already set to `true`, so there is no unwanted logging.

Note: I don't see what @dlemmermann posted but an _initial_ space seems to be missing 
"could not be initialized..."
-->
" could not be initialized..."

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PR: https://git.openjdk.java.net/jfx/pull/693