Draw correctly background images in ref tests

[calixteman]

It's a workaround for bug https://bugzilla.mozilla.org/show_bug.cgi?id=1844414. It should be reverted (in order to avoid a perf penalty) once the bug is fixed in Firefox.

[Snuffleupagus]

r=me, with passing (or improving) tests; thank you!

[calixteman]

/botio test

[moz-tools-bot]

From: Bot.io (Linux m4)

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Received

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

Live output at: http://54.241.84.105:8877/e61dbf561e7f463/output.txt

[moz-tools-bot]

From: Bot.io (Windows)

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Received

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

Live output at: http://54.193.163.58:8877/4db3bbb681dbe68/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Failed

Full output at http://54.241.84.105:8877/e61dbf561e7f463/output.txt

Total script time: 25.40 mins

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

  different ref/snapshot: 16

Image differences available at: http://54.241.84.105:8877/e61dbf561e7f463/reftest-analyzer.html#web=eq.log

[moz-tools-bot]

From: Bot.io (Windows)

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Failed

Full output at http://54.193.163.58:8877/4db3bbb681dbe68/output.txt

Total script time: 38.78 mins

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

  different ref/snapshot: 21

Image differences available at: http://54.193.163.58:8877/4db3bbb681dbe68/reftest-analyzer.html#web=eq.log

[calixteman]

/botio makeref

[moz-tools-bot]

From: Bot.io (Linux m4)

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Received

Command cmd_makeref from @calixteman received. Current queue size: 0

Live output at: http://54.241.84.105:8877/6b5eabd16670032/output.txt

[moz-tools-bot]

From: Bot.io (Windows)

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Received

Command cmd_makeref from @calixteman received. Current queue size: 0

Live output at: http://54.193.163.58:8877/0d22b41a7b978dd/output.txt

[moz-tools-bot]

From: Bot.io (Linux m4)

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Success

Full output at http://54.241.84.105:8877/6b5eabd16670032/output.txt

Total script time: 20.53 mins

• Lint: Passed
• Make references: Passed
• Check references: Passed

[moz-tools-bot]

From: Bot.io (Windows)

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Success

Full output at http://54.193.163.58:8877/0d22b41a7b978dd/output.txt

Total script time: 25.61 mins

• Lint: Passed
• Make references: Passed
• Check references: Passed