Roll gn from 20806f79c6b4 to feafd1012a32

If this roll has caused a breakage, revert this CL and stop the roller
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https://autoroll.skia.org/r/gn-dart-sdk
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Cq-Include-Trybots: luci.dart.try:dart-sdk-linux-try;luci.dart.try:dart-sdk-mac-try;luci.dart.try:dart-sdk-mac-arm64-try;luci.dart.try:dart-sdk-win-try
Change-Id: If9ed533def99d7974a992da53971e23364399c1a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/392300
Reviewed-by: Ryan Macnak <[email protected]>
Commit-Queue: Ryan Macnak <[email protected]>
Reviewed-by: Brian Quinlan <[email protected]>

Author: DEPS Autoroller

DEPS

@@ -79,7 +79,7 @@ vars = {
   "clang_version": "git_revision:3928edecfbd116d56bbe7411365d50bb567380a1",
 
   # https://chrome-infra-packages.appspot.com/p/gn/gn
-  "gn_version": "git_revision:20806f79c6b4ba295274e3a589d85db41a02fdaa",
+  "gn_version": "git_revision:feafd1012a32c05ec6095f69ddc3850afb621f3a",
 
   "reclient_version": "git_revision:c7349324c93c6e0d85bc1e00b5d7526771006ea0",
   "download_reclient": True,