Roll src/third_party/pdfium afc869eaff5b..595e98f87513 (6 commits)

https://pdfium.googlesource.com/pdfium.git/+log/afc869eaff5b..595e98f87513

git log afc869eaff5b..595e98f87513 --date=short --first-parent --format='%ad %ae %s'
2020-04-08 thestig@chromium.org Add FPDFFormFillEmbedderTest.HasFormFieldAtPointForXFADoc.
2020-04-08 thestig@chromium.org Add a <medium> to simple_xfa.{in,pdf}.
2020-04-08 thestig@chromium.org Add FPDFFormFillEmbedderTest.KeyPressWithNoFocusedAnnot.
2020-04-08 amit@pspdfkit.com Fix FindPageIndex() search algorithm.
2020-04-08 thestig@chromium.org Roll v8/ 1668abddd..5deecef68 (111 commits)
2020-04-07 tsepez@chromium.org Cover CJX_Script::stateless() from JavaScript test

Created with:
  gclient setdep -r src/third_party/pdfium@595e98f87513

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/+/master/autoroll/README.md

Bug: None
Tbr: pdfium-deps-rolls@chromium.org
Change-Id: Ia1211074f63cbbdb5a60241bf9373c33341ae77f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2142482Reviewed-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@{#757594}

DEPS

@@ -195,7 +195,7 @@ 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': 'afc869eaff5badd31f06eedb5cbd5f269e8db6bb',
+  'pdfium_revision': '595e98f8751373b20ab56a30fcf46028db300fad',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling BoringSSL
   # and whatever else without interference from each other.