Avoid null ExpansionFactor in type1 fonts (follow-up of #15289)

[calixteman]

No description provided.

[Snuffleupagus]

r=me, with a comment similar to the one in the CFFParser and all tests passing; thank you!

[calixteman]

/botio test

[pdfjsbot]

From: Bot.io (Linux m4)

---

Received

Command cmd_test from @calixteman received. Current queue size: 1

Live output at: http://54.241.84.105:8877/86c3744a277d473/output.txt

[pdfjsbot]

From: Bot.io (Windows)

---

Received

Command cmd_test from @calixteman received. Current queue size: 1

Live output at: http://54.193.163.58:8877/ca733fa5f0acdf7/output.txt

[pdfjsbot]

From: Bot.io (Linux m4)

---

Failed

Full output at http://54.241.84.105:8877/86c3744a277d473/output.txt

Total script time: 26.15 mins

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

  different ref/snapshot: 7
  different first/second rendering: 1

Image differences available at: http://54.241.84.105:8877/86c3744a277d473/reftest-analyzer.html#web=eq.log

[pdfjsbot]

From: Bot.io (Windows)

---

Failed

Full output at http://54.193.163.58:8877/ca733fa5f0acdf7/output.txt

Total script time: 33.73 mins

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

  different ref/snapshot: 18

Image differences available at: http://54.193.163.58:8877/ca733fa5f0acdf7/reftest-analyzer.html#web=eq.log

[calixteman]

/botio-windows test

[pdfjsbot]

From: Bot.io (Windows)

---

Received

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

Live output at: http://54.193.163.58:8877/b77fafb7482314c/output.txt

[pdfjsbot]

From: Bot.io (Windows)

---

Failed

Full output at http://54.193.163.58:8877/b77fafb7482314c/output.txt

Total script time: 32.69 mins

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

  different ref/snapshot: 15

Image differences available at: http://54.193.163.58:8877/b77fafb7482314c/reftest-analyzer.html#web=eq.log