Roll src/third_party/pdfium/ 0ca160fbf..cf7ac1952 (2 commits).

https://pdfium.googlesource.com/pdfium.git/+log/0ca160fbf31a..cf7ac195266f

$ git log 0ca160fbf..cf7ac1952 --date=short --no-merges --format='%ad %ae %s'
2016-09-08 tsepez explicit operator bool for CFX_RetainPtr and CFX_CountRef
2016-09-08 weili Reland of Fix leaked internal font

TBR=dsinclair@chromium.org

Review-Url: https://codereview.chromium.org/2328793002
Cr-Commit-Position: refs/heads/master@{#417469}

DEPS

@@ -60,7 +60,7 @@ 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': '0ca160fbf31a7408df282823f7a3d4cbb5f386a1',
+  'pdfium_revision': 'cf7ac195266fe05f7548c531df32c2b4aa4b5608',
   # 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.