Roll PDFium from b70f99dcd334 to 1553832ddd6c (4 revisions)

https://pdfium.googlesource.com/pdfium.git/+log/b70f99dcd334..1553832ddd6c

2020-08-10 tsepez@chromium.org Remove CFWL_WidgetMrg::SetOwner().
2020-08-10 tsepez@chromium.org Make CFWL_WidgetProperties::m_pParent a const member.
2020-08-10 thestig@chromium.org Limit the input size to pdf_scanlinecompositor_fuzzer.
2020-08-10 tsepez@chromium.org Encapsulate CFWL_Widget.

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 pdfium-deps-rolls@chromium.org on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

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

Bug: chromium:1113870
Tbr: pdfium-deps-rolls@chromium.org
Change-Id: I638590cdb70356cdbb8af2d355d07ea751c65e8a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2347311Reviewed-by: 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/master@{#796615}

DEPS

@@ -215,7 +215,7 @@ vars = {
   # 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': 'b70f99dcd33477cd588e7758fa5c2af345a172f8',
+  'pdfium_revision': '1553832ddd6cd96d6278c84c8b557a0ce6cd9bd7',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling BoringSSL
   # and whatever else without interference from each other.