Roll src/third_party/pdfium/ 9a635e812..a17ac192c (4 commits)

https://pdfium.googlesource.com/pdfium.git/+log/9a635e812788..a17ac192c043

$ git log 9a635e812..a17ac192c --date=short --no-merges --format='%ad %ae %s'
2018-03-21 hnakashima Explain how CPDF_Page::GetDisplayMatrix() inverts y.
2018-03-21 thestig Fix some param names in the public API.
2018-03-21 thestig Change FXSYS_RGB() to FXSYS_BGR().
2018-03-21 thestig Change FXSYS_Get{R,G,B}Value()'s input param to BGR.

Created with:
  roll-dep src/third_party/pdfium


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: I44753f4c9360d3816f38f60622e5d3cef55abddd
Reviewed-on: https://chromium-review.googlesource.com/973462
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@{#544708}

DEPS

@@ -103,7 +103,7 @@ 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': '9a635e8127880dd93b2abc5e8da6a45046d35e31',
+  'pdfium_revision': 'a17ac192c043a6bce51e16cf7cd076087c78d9a9',
   # 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.