Roll src/third_party/pdfium/ 3128d1c45..d18b86743 (1 commit).

https://pdfium.googlesource.com/pdfium.git/+log/3128d1c45d8b..d18b8674378b

$ git log 3128d1c45..d18b86743 --date=short --no-merges --format='%ad %ae %s'
2017-01-10 tsepez Remove some CFX_ArrayTemplate in fpdfapi and fpdfdoc

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

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls

TBR=dsinclair@chromium.org

Review-Url: https://codereview.chromium.org/2622893004
Cr-Commit-Position: refs/heads/master@{#442664}

DEPS

@@ -64,7 +64,7 @@ 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': '3128d1c45d8bc313abb8aae151f86bbe62c52e56',
+  'pdfium_revision': 'd18b8674378b104a9b5bb1f015e3f92fc174673e',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling openmax_dl
   # and whatever else without interference from each other.