Consistently remove the "visibilitychange" listener in PDFViewer (PR 14388 follow-up)

[Snuffleupagus]

By always removing the "visibilitychange" listener in the PDFViewer.#onePageRenderedOrForceFetch-method we can (ever so slightly) reduce duplication in the code.

[Snuffleupagus]

/botio-linux preview

[moz-tools-bot]

From: Bot.io (Linux m4)

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Received

Command cmd_preview from @Snuffleupagus received. Current queue size: 0

Live output at: http://54.241.84.105:8877/f838fd31396a6f1/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/f838fd31396a6f1/output.txt

Total script time: 1.48 mins

Published

• Viewer: http://54.241.84.105:8877/f838fd31396a6f1/web/viewer.html
• Viewer (legacy): http://54.241.84.105:8877/f838fd31396a6f1/legacy/web/viewer.html

[Snuffleupagus]

/botio integrationtest

[moz-tools-bot]

From: Bot.io (Linux m4)

---

Received

Command cmd_integrationtest from @Snuffleupagus received. Current queue size: 0

Live output at: http://54.241.84.105:8877/903ba7df511d8d9/output.txt

[moz-tools-bot]

From: Bot.io (Windows)

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Received

Command cmd_integrationtest from @Snuffleupagus received. Current queue size: 0

Live output at: http://54.193.163.58:8877/f72ed9baff81a46/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/903ba7df511d8d9/output.txt

Total script time: 5.91 mins

• Integration Tests: Passed

[moz-tools-bot]

From: Bot.io (Windows)

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Success

Full output at http://54.193.163.58:8877/f72ed9baff81a46/output.txt

Total script time: 17.97 mins

• Integration Tests: Passed

[timvandermeij]

Thank you for simplifying this!