Update V8 to version 7.1.189.

Summary of changes available at:
https://chromium.googlesource.com/v8/v8/+log/c9fae1c2..4034a5cf

Please follow these instructions for assigning/CC'ing issues:
https://github.com/v8/v8/wiki/Triaging%20issues

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

CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel;luci.chromium.try:linux_optional_gpu_tests_rel;luci.chromium.try:mac_optional_gpu_tests_rel;luci.chromium.try:win_optional_gpu_tests_rel;luci.chromium.try:android_optional_gpu_tests_rel

[email protected],[email protected]

Change-Id: I585d662022f0482c02d51189c8972d52d0cfd130
Reviewed-on: https://chromium-review.googlesource.com/1249302
Reviewed-by: 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@{#594687}
diff --git a/DEPS b/DEPS
index 9354804..35446ed 100644
--- a/DEPS
+++ b/DEPS
@@ -109,7 +109,7 @@
   # 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': 'c9fae1c265ef71bef4a8805e64633d0a62b852c2',
+  'v8_revision': '4034a5cfc80ef30c05c31ac733b880d9ec1241fa',
   # 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.