Roll PDFium from 4b17b5ffd2ce to 6aadd6ed35dc (3 revisions)

https://pdfium.googlesource.com/pdfium.git/+log/4b17b5ffd2ce..6aadd6ed35dc

2025-10-10 ahaas@google.com Add type tags to calls to v8::External
2025-10-10 tsepez@chromium.org Roll v8/ 37f82dbb9..7f18b53ba (259 commits)
2025-10-10 hocheung@chromium.org [tools] Fix encode_pdf_filter.py for Python 3.13 compatibility

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/pdfium-autoroll
Please CC dhoss@chromium.org,thestig@chromium.org,thestig@google.com on the revert to ensure that a human
is aware of the problem.

To file a bug in PDFium: https://bugs.chromium.org/p/pdfium/issues/entry
To file a bug in Chromium: https://bugs.chromium.org/p/chromium/issues/entry

To report a problem with the AutoRoller itself, please file a bug:
https://issues.skia.org/issues/new?component=1389291&template=1850622

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

Bug: chromium:440472007
Tbr: thestig@google.com
Change-Id: Ib174976f5a62acfa8a03107ddd40c330b0e7ec5d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/7033571
Bot-Commit: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Commit-Queue: chromium-autoroll <chromium-autoroll@skia-public.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1528465}
diff --git a/DEPS b/DEPS
index 7911c57..4eb5986 100644
--- a/DEPS
+++ b/DEPS
@@ -325,7 +325,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling PDFium
   # and whatever else without interference from each other.
-  'pdfium_revision': '4b17b5ffd2ce0a5f6850f95e32bb1274159a7842',
+  'pdfium_revision': '6aadd6ed35dcf9abbef5fb8ad13ac81d6ed92566',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling BoringSSL
   # and whatever else without interference from each other.
diff --git a/third_party/pdfium b/third_party/pdfium
index 4b17b5f..6aadd6e 160000
--- a/third_party/pdfium
+++ b/third_party/pdfium
@@ -1 +1 @@
-Subproject commit 4b17b5ffd2ce0a5f6850f95e32bb1274159a7842
+Subproject commit 6aadd6ed35dcf9abbef5fb8ad13ac81d6ed92566