This change is similar to https://github.com/flutter/flutter/issues/82728.  We are using a more recent Chromium ICU fork commit.

See for reference: https://chromium.googlesource.com/chromium/deps/icu

Flutter needs to use a reasonably recent version of the ICU library. The Chromium's fork of ICU, which is in use in Flutter as well, has taken in a few updates since the initial 69.1 release.  This is a request to bring them in by updating ICU library version in the `DEPS` file to https://chromium.googlesource.com/chromium/deps/icu/+/2a822c5626ab1ed40366758e4740b4f0ea40237d, which is the current HEAD of the `main` branch in Chromium's ICU library fork.

Update the DEPS file in github.com/flutter/engine to use the commit ID `2a822c5626ab1ed40366758e4740b4f0ea40237d`.

This is the same commit ID as used by Chromium M93, making it easier to share the ICU data on systems where it is possible to deduplicate identical libraries, such as Fuchsia.

Fixes: #flutter/flutter/87073

https://dart.googlesource.com/sdk.git/+log/b410651bd18e..f82b36d0b4f0

2021-07-20 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.14.0-337.0.dev
2021-07-20 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.14.0-336.0.dev
2021-07-19 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.14.0-335.0.dev
2021-07-19 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.14.0-334.0.dev
2021-07-19 dart-luci-ci-builder@dart-ci.iam.gserviceaccount.com Version 2.14.0-333.0.dev

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://autoroll.skia.org/r/dart-sdk-flutter-engine
Please CC garyq@google.com,dart-vm-team@google.com,zra@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/main/autoroll/README.md

* Revert "Roll Dart SDK from 87a4768078b2 to 2abf053a8e9a (1 revision) (#27489)"

This reverts commit 04e2b8a0.

* Revert "Roll Dart SDK from 207232b5abe0 to 87a4768078b2 (5 revisions) (#27476)"

This reverts commit 76eb77a7.