Switch PDFium roller to Gerrit
Switch PDFium roller to Gerrit

Bug: skia:5787
Change-Id: Iaae7b331267156a2884b81995891ecb81b41f44e
Reviewed-on: https://skia-review.googlesource.com/13241
Reviewed-by: Ravi Mistry <9fa2e7438b8cb730f96b74865492597170561628@google.com>
Commit-Queue: Eric Boren <0e499112533c8544f0505ea0d08394fb5ad7d8fa@google.com>

google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot,google/skia-buildbot