Roll third_party/zlib/ 8c371ad77..39b4a6260 (5 commits)

https://chromium.googlesource.com/chromium/src/third_party/zlib.git/+log/8c371ad77b83..39b4a6260702

Created with:
  roll-dep third_party/zlib

TBR=dsinclair@chromium.org

Change-Id: Id5352f7d921e8d752a7f70ee18b11026661f2165
Reviewed-on: https://pdfium-review.googlesource.com/36892
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/DEPS b/DEPS
index ef9903a..e140e78 100644
--- a/DEPS
+++ b/DEPS
@@ -35,7 +35,7 @@
   'trace_event_revision': '0e9a47d74970bee1bbfc063c47215406f8918699',
   'v8_revision': '9cf8abb7ce7e3a3152fb71d0e87678e64f7ab0c8',
   'yasm_source_revision': 'b98114e18d8b9b84586b10d24353ab8616d4c5fc',
-  'zlib_revision': '8c371ad77b836c02e44006dc2dc77c5d6d910861',
+  'zlib_revision': '39b4a6260702da4c089eca57136abf40a39667e9',
 }
 
 deps = {