Roll src/third_party/pdfium/ 7e4e63b04..d54c9d8df (1 commit).

https://pdfium.googlesource.com/pdfium.git/+log/7e4e63b04f87..d54c9d8df151

$ git log 7e4e63b04..d54c9d8df --date=short --no-merges --format='%ad %ae %s'
2016-09-02 jaepark Remove unused IPDFSDK_AnnotHandler::OnDrawSleep.

TBR=dsinclair@chromium.org

Review-Url: https://codereview.chromium.org/2304283002
Cr-Commit-Position: refs/heads/master@{#416354}

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': '7e4e63b04f87c690b017c43ebbb3218eb30c459a',
+  'pdfium_revision': 'd54c9d8df1511f6abac291ec2ec660cef372d9d3',
   # 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.