Confirmed to be a regression. Bisecting.

Bisect points at this CL as culprit:

https://pdfium-review.googlesource.com/c/pdfium/+/15072
"Cleanup font defines

Use methods to match font information; cleanup some font code."

That's too far back to rollback, we should find the bug and fix it forward instead.

Can you reproduce this bug with pdfium_test? Maybe we can write a regression test.

Yes, I found the commit testing with pdfium_test.

In https://pdfium-review.googlesource.com/c/pdfium/+/15072/3/core/fxge/cfx_fontmapper.cpp, the old code had a block at lines 547-550 that probably should not have been fully removed.

Actually, I meant a very similar looking block at lines 602-605.

The following revision refers to this bug:
  https://pdfium.googlesource.com/pdfium/+/71501b5226ca7cbedbc5f972dd3d54d3d5de4d98

commit 71501b5226ca7cbedbc5f972dd3d54d3d5de4d98
Author: Lei Zhang <thestig@chromium.org>
Date: Tue May 22 16:48:17 2018

Add test case for a font substitution regression.

BUG= chromium:820345 

Change-Id: Ia3adb6a7565e12f3d5e129e2babb4b8628028269
Reviewed-on: https://pdfium-review.googlesource.com/32810
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

[add] https://crrev.com/71501b5226ca7cbedbc5f972dd3d54d3d5de4d98/testing/resources/pixel/bug_820345_expected_mac.pdf.0.png
[add] https://crrev.com/71501b5226ca7cbedbc5f972dd3d54d3d5de4d98/testing/resources/pixel/bug_820345.in
[add] https://crrev.com/71501b5226ca7cbedbc5f972dd3d54d3d5de4d98/testing/resources/pixel/bug_820345_expected.pdf.0.png

The following revision refers to this bug:
  https://pdfium.googlesource.com/pdfium/+/a2edb51dcd4551a021438cbb8b6e1b5172b3ca18

commit a2edb51dcd4551a021438cbb8b6e1b5172b3ca18
Author: Lei Zhang <thestig@chromium.org>
Date: Tue May 22 16:50:49 2018

Fix a regression with missing text.

Commit 10e1f05a incorrectly removed a font weight sanitizing step in the
font substitution code.

BUG= chromium:820345 

Change-Id: I876f65a5649270648616f561eaad17ee333b9a9e
Reviewed-on: https://pdfium-review.googlesource.com/32832
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

[add] https://crrev.com/a2edb51dcd4551a021438cbb8b6e1b5172b3ca18/testing/resources/pixel/bug_820345_expected_win.pdf.0.png
[modify] https://crrev.com/a2edb51dcd4551a021438cbb8b6e1b5172b3ca18/core/fxge/cfx_fontmapper.cpp
[modify] https://crrev.com/a2edb51dcd4551a021438cbb8b6e1b5172b3ca18/testing/resources/pixel/bug_820345_expected.pdf.0.png

Should be fixed in 68.0.3438.0 and newer.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ea79917de379fabc979747fbbf41a032550ddf9b

commit ea79917de379fabc979747fbbf41a032550ddf9b
Author: pdfium-chromium-autoroll <pdfium-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Date: Tue May 22 19:30:10 2018

Roll src/third_party/pdfium/ 366df7fd6..7f472cd8a (7 commits)

https://pdfium.googlesource.com/pdfium.git/+log/366df7fd6e6b..7f472cd8abe4

$ git log 366df7fd6..7f472cd8a --date=short --no-merges --format='%ad %ae %s'
2018-05-22 thestig Remove useless CPDFSDK_Widget::SetDefaultValue().
2018-05-22 thestig Fix a regression with missing text.
2018-05-22 thestig Add test case for a font substitution regression.
2018-05-22 npm Order CHKs in alphabetical order within each file
2018-05-22 thestig Remove JBIG2_memcpy() and JBIG2_memset().
2018-05-22 thestig Remove return value from CJBig2_Image::SetPixel().
2018-05-22 thestig Fix method style in JBig2_Image.

Created with:
  roll-dep src/third_party/pdfium
BUG= chromium:820345 , chromium:820345 


The AutoRoll server is located here: https://pdfium-roll.skia.org

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.


TBR=dsinclair@chromium.org

Change-Id: Ie1d03549493d95c1387d28bf3ae85ccfb087aafa
Reviewed-on: https://chromium-review.googlesource.com/1069299
Commit-Queue: pdfium-chromium-autoroll <pdfium-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Reviewed-by: pdfium-chromium-autoroll <pdfium-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#560731}
[modify] https://crrev.com/ea79917de379fabc979747fbbf41a032550ddf9b/DEPS

 Issue 849611  has been merged into this issue.

 Issue 803170  has been merged into this issue.

 Issue 807250  has been merged into this issue.