Roll third_party/zlib/ 2231b7c84..efd9399ae (2 commits)

https://chromium.googlesource.com/chromium/src/third_party/zlib.git/+log/2231b7c84b44..efd9399ae013

Created with:
  roll-dep third_party/zlib

Change-Id: Ib2938ab959eb47bc1e1864f5cd9f7a2ae201c66c
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/88692
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/DEPS b/DEPS
index fc737f8..0208029 100644
--- a/DEPS
+++ b/DEPS
@@ -140,7 +140,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling zlib
   # and whatever else without interference from each other.
-  'zlib_revision': '2231b7c84b443385f2bd65dd6c46b3c7b957eae1',
+  'zlib_revision': 'efd9399ae01364926be2a38946127fdf463480db',
 }
 
 # Only these hosts are allowed for dependencies in this DEPS file.