Roll third_party/icu/ d879aac97..cd9f9a949 (4 commits)

https://chromium.googlesource.com/chromium/deps/icu.git/+log/d879aac9717d..cd9f9a9495b1

Created with:
  roll-dep third_party/icu

Change-Id: Ia62d317d1bfb3acaf15adf2fc3a4fbcaead030da
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/80074
Reviewed-by: Hui Yingst <nigi@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>

DEPS

diff --git a/DEPS b/DEPS
index 818f8b1..0577f99 100644
--- a/DEPS
+++ b/DEPS
@@ -73,7 +73,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling icu
   # and whatever else without interference from each other.
-  'icu_revision': 'd879aac9717d15679125cfe8c26b482006f107f3',
+  'icu_revision': 'cd9f9a9495b1978ded709c248e467e7f5a74ea0a',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling instrumented_lib
   # and whatever else without interference from each other.