Update V8 to version 9.4.28.

Summary of changes available at:
https://chromium.googlesource.com/v8/v8/+log/b7f54778..6cfe6347

Please follow these instructions for assigning/CC'ing issues:
https://v8.dev/docs/triage-issues

Please close rolling in case of a roll revert:
https://v8-roll.appspot.com/
This only works with a Google account.

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CQ_INCLUDE_TRYBOTS=luci.chromium.try:linux_optional_gpu_tests_rel
CQ_INCLUDE_TRYBOTS=luci.chromium.try:mac_optional_gpu_tests_rel
CQ_INCLUDE_TRYBOTS=luci.chromium.try:win_optional_gpu_tests_rel
CQ_INCLUDE_TRYBOTS=luci.chromium.try:android_optional_gpu_tests_rel

R=hablich@chromium.org,vahl@chromium.org,v8-waterfall-sheriff@grotations.appspotmail.com

Change-Id: Ic3ca1e8d6bd4888c98ab2802d60258ec672b0929
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3045598
Bot-Commit: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#904345}
diff --git a/DEPS b/DEPS
index 23ddfcc..bb37999 100644
--- a/DEPS
+++ b/DEPS
@@ -232,7 +232,7 @@
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.
-  'v8_revision': 'b7f547783892aca7d820c24288f8c86e1b47f8ec',
+  'v8_revision': '6cfe6347b6a4ec9fa98fbd43eaaa20d2c0b56c60',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling swarming_client
   # and whatever else without interference from each other.