Avoid re-parsing global images that failed decoding (issue 18042, PR 17428 follow-up)

[Snuffleupagus]

For images that failed to decode once we want to avoid a pointless round-trip to the main-thread, which could otherwise happen for globally cached images.

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Please note: Submitted as a "draft", since I'm not keen on making these changes without test-coverage.

Given the lack of a real-world PDF document, since none was provided, I've tried to manually create a broken one. However, I obviously cannot tell if it properly covers the original issue.

[Snuffleupagus]

/botio test

[moz-tools-bot]

From: Bot.io (Linux m4)

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Received

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

Live output at: http://54.241.84.105:8877/680322ba53bd9ff/output.txt

[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/b3d520195b38933/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Failed

Full output at http://54.241.84.105:8877/680322ba53bd9ff/output.txt

Total script time: 27.47 mins

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

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

Image differences available at: http://54.241.84.105:8877/680322ba53bd9ff/reftest-analyzer.html#web=eq.log

[moz-tools-bot]

From: Bot.io (Windows)

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Failed

Full output at http://54.193.163.58:8877/b3d520195b38933/output.txt

Total script time: 42.82 mins

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

  errors: 1
  different ref/snapshot: 8

Image differences available at: http://54.193.163.58:8877/b3d520195b38933/reftest-analyzer.html#web=eq.log

[plantago]

I tested the changes in this PR with the pdf files I was having problems with.
Everything works fine now.

[timvandermeij]

/botio-linux preview

[moz-tools-bot]

From: Bot.io (Linux m4)

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Received

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

Live output at: http://54.241.84.105:8877/728546f044e3c2b/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/728546f044e3c2b/output.txt

Total script time: 1.16 mins

Published

• Viewer: http://54.241.84.105:8877/728546f044e3c2b/web/viewer.html
• Viewer (legacy): http://54.241.84.105:8877/728546f044e3c2b/legacy/web/viewer.html

[timvandermeij]

Looks good to me; the included PDF file seems to cover the problem well, also given that the original reporter shared that this patch solved the issue. Thanks!

[calixteman]

LGTM for me either. Thank you for doing this.