roll: gn

From: git_revision:dfcbc6fed0a8352696f92d67ccad54048ad182b3
To: git_revision:64b3b9401c1c3ed5f3c43c1cac00b91f83597ab8

CQ-Do-Not-Cancel-Tryjobs: true
Roller-URL: https://ci.chromium.org/b/8852173602563318192
Cq-Cl-Tag: roller-builder:gn-roller
Cq-Cl-Tag: roller-bid:8852173602563318192
CQ-Do-Not-Cancel-Tryjobs: true
Change-Id: I3ebdc2f59ee0c85a2f84129f34dd8817b3066009
Reviewed-on: https://pigweed-review.googlesource.com/c/pigweed/pigweed/+/37700
Reviewed-by: Pigweed Roller <pigweed-roller@pigweed.google.com.iam.gserviceaccount.com>
Commit-Queue: Pigweed Roller <pigweed-roller@pigweed.google.com.iam.gserviceaccount.com>
diff --git a/pw_env_setup/py/pw_env_setup/cipd_setup/pigweed.json b/pw_env_setup/py/pw_env_setup/cipd_setup/pigweed.json
index 0018609..316448e 100644
--- a/pw_env_setup/py/pw_env_setup/cipd_setup/pigweed.json
+++ b/pw_env_setup/py/pw_env_setup/cipd_setup/pigweed.json
@@ -2,7 +2,7 @@
   {
     "path": "gn/gn/${os}-${arch=amd64,arm64}",
     "tags": [
-      "git_revision:dfcbc6fed0a8352696f92d67ccad54048ad182b3"
+      "git_revision:64b3b9401c1c3ed5f3c43c1cac00b91f83597ab8"
     ]
   },
   {