Ensure that the viewer waits for the library to complete loading (issue 17228)

[Snuffleupagus]

This should hopefully fix #17228, by tweaking the build scripts to give the GENERIC viewer something to await to avoid breaking third-party users of the standalone viewer components.

[Snuffleupagus]

/botio-linux preview

[moz-tools-bot]

From: Bot.io (Linux m4)

---

Received

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

Live output at: http://54.241.84.105:8877/790f86210007488/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/790f86210007488/output.txt

Total script time: 1.37 mins

Published

• Viewer: http://54.241.84.105:8877/790f86210007488/web/viewer.html
• Viewer (legacy): http://54.241.84.105:8877/790f86210007488/legacy/web/viewer.html

[Snuffleupagus]

/botio test

[moz-tools-bot]

From: Bot.io (Windows)

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Received

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

Live output at: http://54.193.163.58:8877/a20c848edcea568/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

---

Received

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

Live output at: http://54.241.84.105:8877/36fcd84350ab45e/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Failed

Full output at http://54.241.84.105:8877/36fcd84350ab45e/output.txt

Total script time: 24.72 mins

• Font tests: Passed
• Unit tests: Passed
• Integration Tests: Passed
• Regression tests: FAILED

  different ref/snapshot: 19
  different first/second rendering: 1

Image differences available at: http://54.241.84.105:8877/36fcd84350ab45e/reftest-analyzer.html#web=eq.log

[moz-tools-bot]

From: Bot.io (Windows)

---

Failed

Full output at http://54.193.163.58:8877/a20c848edcea568/output.txt

Total script time: 26.66 mins

• Font tests: FAILED
• Unit tests: Passed
• Integration Tests: FAILED
• Regression tests: FAILED

  different ref/snapshot: 16
  different first/second rendering: 1

Image differences available at: http://54.193.163.58:8877/a20c848edcea568/reftest-analyzer.html#web=eq.log

[Snuffleupagus]

Locally I've tried changing

pdf.js/examples/components/simpleviewer.html

Lines 40 to 41 in 8e5311e

	<script src="../../node_modules/pdfjs-dist/build/pdf.mjs" type="module"></script>
	<script src="../../node_modules/pdfjs-dist/web/pdf_viewer.mjs" type="module"></script>

into

<script type="module">
  import "../../node_modules/pdfjs-dist/build/pdf.mjs";
  import "../../node_modules/pdfjs-dist/web/pdf_viewer.mjs";
</script> 

That failed when testing against master, but worked with this patch.

[timvandermeij]

Let's do this; thank you!