Add new builder for experiment with dynamic modules. (#162855)

This adds a new flavor of android_release_arm64, which enables a build
flag. This is not part of the merge-queue since it's intended for
experimental and internal use at the moment.

Tested locally via `et build --config ci/android_release_arm64_ddm`

This is a first step to get a better gauge of the cost on the build. The
.json is identical to the android_release_arm64 configuration except for
2 new flags added (easier to diff locally). The .ci.yaml has additional
changes to make set this up as no backfill and no release.

cc @jtmcdole @jiahaog @andrewkolos

---------

Co-authored-by: Sigmund Cherem < 2049220+sigmundch@users.noreply.github.com>
https://dart.googlesource.com/external/github.com/flutter/flutter/+/2376fa02f1bee79dea0ee061695e205eed91f89c

DEPS

diff --git a/DEPS b/DEPS
index 2e763d8..ca37c8a 100644
--- a/DEPS
+++ b/DEPS
@@ -239,7 +239,7 @@
 deps = {
   'flutter/engine/src/flutter/third_party/dart': Var('dart_git') + '/sdk' + '@' + '5c6f92fe47e4b7d9e3a3cf4bcd8566c44ebfbe10',
 
-  'flutter': Var('flutter_git') + '/mirrors/flutter' + '@' + '6c9a555e561509d62cb4219d8c3d7991f6c35bcf',
+  'flutter': Var('flutter_git') + '/mirrors/flutter' + '@' + '2376fa02f1bee79dea0ee061695e205eed91f89c',
 
   'flutter/engine/src/flutter/third_party/depot_tools':
   Var('chromium_git') + '/chromium/tools/depot_tools.git' + '@' + '580b4ff3f5cd0dcaa2eacda28cefe0f45320e8f7',
@@ -263,7 +263,7 @@
    Var('chromium_git') + '/external/github.com/google/shaderc' + '@' + '37e25539ce199ecaf19fb7f7d27818716d36686d',
 
   'flutter/engine/src/flutter/third_party/vulkan-deps':
-   Var('chromium_git') + '/vulkan-deps' + '@' + '014f44e134a1de387791bffacc32ff9d8db71176',
+   Var('chromium_git') + '/vulkan-deps' + '@' + '938de304bdcb33049ec39ce45f16223eb6a960b6',
 
   'flutter/engine/src/flutter/third_party/flatbuffers':
    Var('chromium_git') + '/external/github.com/google/flatbuffers' + '@' + '0a80646371179f8a7a5c1f42c31ee1d44dcf6709',

commits.json

diff --git a/commits.json b/commits.json
index 9b73146..545829e 100644
--- a/commits.json
+++ b/commits.json
@@ -1,4 +1,4 @@
 {
-  "flutter":"6c9a555e561509d62cb4219d8c3d7991f6c35bcf",
+  "flutter":"2376fa02f1bee79dea0ee061695e205eed91f89c",
   "flutter/engine/src/flutter/third_party/dart":"5c6f92fe47e4b7d9e3a3cf4bcd8566c44ebfbe10"
 }
\ No newline at end of file